When I had an office job where we tracked our own hours, I would always put down that I worked an extra hour of work each day.
Why would you lie about the number of hours worked?
Because doing that earned me an extra $250 every two weeks. Why would I not do that?
What happens when they find out that you are lying? It is wrong to lie on your time card when your employer is expecting you to be honest and trusts you.
It was long time ago so it doesn't matter.
Well even if you can't get in trouble for that since it was so long ago, it was still wrong to do. If you continue behavior like that at your current job, you are likely to be fired. You need to be honest with your employer about the time you spend at work.