Have you ever looked at something and felt like everything was normal, just to realize that there was a mistake when staring at you? That is exactly the type of challenge we have for you today! Optical illusions are not just joy; They also check your observation level and your brain to handle what your eyes see. So, be ready to bring your sharp vision into testing with this difficult optical illusion with clock! This is an agreement: Imagine looking at a watch. At first glance, everything seems good, the hand is set, the design looks neat and the numbers around the number seem perfectly arranged. But wait! There is a mistake hidden in a clear vision. 
Image credit: Brightside
This is a suggestion to help you: Consider more carefully the numbers on the dial. Still can’t find it? Do not worry; You are not alone. Many people ignore it because their brain quickly filled the gaps or accepted what seemed normal. How to sharpen your observation skills like this need to practice. Here are a few tips to sharpen your observation skills: 1. Spend your time to see details instead of urgent. 2. Look at everything from different angles or distances. 3. Solve riddles, play different games on the spot or try many optical illusions like this. 4. Always ask what you see instead of assuming everything is right. What is the mistake? If you look closely, you will notice that the number 10 is missing on the dial. Instead of the usual string, the number 9 is repeated twice! Difficulties, right? Most people did not discover this immediately because their minds were too familiar with seeing the numbers in a specific order. It is almost your brain to play a trick with you by thinking that everything is fine. 
Image credit: Brightside
Why do we miss such details? The optical illusion like this is very effective that our brain is based on samples and shortcuts. When you look at something familiar like a watch, your brain automatically assumes the numbers will be in the correct order. This mental shortcut helps you process information quickly, but it also makes you miss small details as some repeated. This type of challenge not only checks your vision. It also measures your level of attention to details and your brain quickly catches the inconsistency.
