As a Sudoku enthusiast and gamer, I have come across many individuals who struggle with solving these puzzles. From my experience, I’ve identified common reasons why people fail in Sudoku, which I will share in this post.
People fail in Sudoku for multiple reasons, such as lack of focus, limited knowledge of solving techniques, not double-checking their work, giving up too easily and not using pencil marks. These factors can make it difficult for individuals to see patterns, identify errors and solve the puzzle.
Anyone who finds out these reasons would dramatically improve their game. I hope you can use my tips here to improve your Sudoku skills. So, here are the reasons why people keep failing in Sudoku.

1. Lack of Focus
Solving a Sudoku puzzle requires concentration and attention to detail. Distractions or a lack of focus can make it difficult to see patterns or identify errors.
Puzzles such as Sudoku require your full attention to solve them. Therefore, focusing would make you more accurate and faster when finishing these puzzles.
Some people could get frustrated as they can’t concentrate for a long time on these puzzles. However, the good thing about these puzzles is they improve your concentration skills the more you use them.
In a separate post, I specified that these puzzles are perfect for older adults as Sudoku can engage and keep their brains focused for a couple of hours which, in turn, helps keep their brains active and sharp.
Recommended Read: Have you ever wondered about the benefits of Sudoku puzzles, such as keeping their brains active and sharp? If you are, you may like reading this post: 9 Reasons why Sudoku is Good for Old People?
2. Limited Knowledge of Problem-Solving Techniques
Limited knowledge of solving techniques: Understanding and applying different techniques such as crosshatching, hidden singles, and naked pairs can significantly improve one’s ability to solve a Sudoku puzzle.
Contrary to others, guessing the numbers is a bad idea. Guessing a number can get you off the right track in solving the puzzle.
Instead, focus and learn some Sudoku techniques to help you put the correct numbers in place.
In my case, I was guilty of guessing when I was a beginner, but once I learned different Sudoku-solving techniques, I could finish puzzles quickly and accurately.
Of course, beginners often guess, but once you get to advanced puzzles, guessing becomes counterproductive.

3. Not Double Checking Work
It is easy to make mistakes when solving a Sudoku puzzle, so it is essential to double-check your work to ensure that all of the numbers are placed correctly.
When I was a beginner, I often thought that Sudoku was about finishing the puzzle as fast as possible, but the longer I played the game, it was about enjoying it.
But why am I explaining this? Well, thinking that the game is about speed is one of the most common reasons people don’t double-check their work.
The problem with Sudoku is that early errors can snowball until you realize you must start over to finish the puzzle.
In turn, this makes them slower in finishing.
Always double-check your work. Check your notes, which we will discuss later how to do. That way, you will be accurately finishing Sudoku puzzles.
Of course, speed could be your priority. But beginners are advised not to think of speed as you first need to be accurate before trying to solve a puzzle fast.
Slowly master the Sudoku techniques I shared at the start of this post, and you will surely get better at the game.

4. Giving Up Too Easily
Sudoku puzzles can be challenging and may require persistence and patience. Unfortunately, some people may give up too easily if they do not progress.
This is the problem.
Giving up too fast could let you skip the puzzles you should be able to finish, provided you give more time to it.
I must admit that I was like this when I started. First, I thought I should guess and check if the numbers were right. If I can’t guess, the puzzle isn’t for me.
This is the wrong approach, and I don’t want anyone to be like me. So, why not give an extra few minutes to focus on the puzzle fully? Maybe research new skills and techniques to be better like what you’re doing now?
Remember that you will only get better at solving Sudoku puzzles if you work on the puzzles that challenge you.
5. Not Using Notes
Notes or pencil marks are small numbers written in the squares to help keep track of the possible numbers that can go in a specific square.
Not using pencil marks can make the puzzle more difficult and increase the chance of making mistakes.
Ever wonder why many people use pencils to solve Sudoku puzzles? This is because they put small notes to visualize the numbers that fit those boxes.
While beginners guess numbers, advanced Sudoku puzzlers write the probability of each number for each box.
Notes are a great way to help your brain do what it is good at, which is analyzing. Rather than memorizing the possibilities for each box, it is better to write them down and write down the things you discovered while analyzing your puzzle.
This simple tip will significantly improve your Sudoku games in the future.
6. Putting Too Many Notes
As we’ve discussed earlier, putting pencil marks or notes helps solve Sudoku puzzles. The problem arises when there are too many notes that it becomes too cluttered instead of being useful.
Since the space for the puzzle is limited, too many notes can make the puzzle more confusing than it is.
As a rule of thumb, do not put more than four possible numbers on each box. This is a rule I use when working on complicated Sudoku puzzles.
This also helps me focus on finding the blank boxes where I can put the correct number immediately.
Sometimes, it is better to do the opposite: list the numbers that shouldn’t be in the box. This method works mainly if you’re out of options.
Choosing which method works better for you depends on your preference. However, as a rule of thumb, the method that would use fewer notes should be the one you’re using.
7. Not Looking at the Bigger Picture
Another reason why people may fail to solve a Sudoku puzzle is because they fail to see the bigger picture. This can happen when a person becomes too focused on the individual squares and numbers rather than considering how they all fit together. By failing to see the bigger picture, it can be difficult to identify patterns or make connections that would otherwise be obvious.
For example, suppose a person is trying to place a number in a specific square but is not considering how that number may affect the rest of the puzzle. In that case, they may end up making mistakes that would have been avoided if they had taken a step back to look at the entire puzzle.
To solve a Sudoku puzzle, it is essential to constantly refer back to the entire puzzle, not just the individual squares. This will help to identify patterns and make it easier to see how the numbers fit together.
I often see beginners do this, thinking they are slowly solving the puzzles by focusing on the small squares or the edges.
While this could help, it is a good idea to check the bigger picture from time to time. Why? Because there are times when the number fit the small picture, but once you get bigger, you realize that what you placed initially is wrong.
This could make you start over again, which is what we are preventing.
8. Not Looking for Hidden Pairs
Do you want a simple technique that could improve your Sudoku game to its fullest? Then you should learn about Hidden pairs.
Another reason why people may fail to solve a Sudoku puzzle is that they forget about the missing pair technique. This technique identifies pairs of numbers that can only go in specific squares within a row, column, or region. By eliminating the other possibilities, it becomes easier to place the remaining numbers in the correct squares.
This technique works well with pencil marking.
For example, if a person sees that the number 5 can only be placed in two specific squares within a row, then it is clear that the other number that can be placed in those two squares is not 5. This eliminates the different possibilities and makes it easier to identify other numbers in the correct squares.
It is essential to use this technique in combination with other methods, such as crosshatching and hidden singles. It is also useful to know the possible number combinations in a row, column, or region to spot the missing pairs quickly. As a result, this technique can be an effective way to simplify the problem and solve the puzzle more efficiently.

9. Not Working on the Obvious First
Often, you may see easy groups, columns, or rows which has only 1-2 blanks.
If you spot these, put the numbers right away.
I can’t count how often I have seen beginners skip this step. But to be honest, this should be the first technique a beginner should know to solve Sudoku puzzles.
This is why I placed this last since I hope you would see it as very important.
Also, remember that the more you solve the puzzle, the easier it will be to solve the remaining blanks.
I hope these tips help you and keep puzzling!
What’s Next? have you considered playing chess? How is it different from Sudoku? I created a post discussing this, which you can read if interested. Here is the link: Sudoku vs. Chess.