ASP.NET button, placed in code behind, isn’t fired at first click

For a project i needed to create a button in my code behind file of my ASP.NET User Control. But when I’ve added the code to the handler of the button’s click event. I noticed that my button didn’t execute my code on the first click on the button.

To find the solution / problem of what may cause this problem I used Google, and I found this interesting article that explained and resolved the problem Article