In my 20+ years of experience in the Information Technology (IT), it still amazes me how few people are willing to admit they have made a mistake.
IT is very ego driven and I believe that is a part of why people are unwilling to admit they made a mistake or something they did caused an issue. I generally do not care if a mistake is made (as long as it is not repeated), but I am not cool with not admitting or blaming others for your mistake.
All systems leave a log or a sign that something has been changed, if you fess up, it makes correcting the mistake much easier, if you don't it takes twice as long to fix the mistake that was made.
What also makes me shake my head is those who will blame others or attempt to point to a different problem to avoid being caught or held responsible. They must think that others are really stupid or they Houdini and can pull the wool over ones eyes.
You will make mistakes and you can learn from those mistakes. In fact, I don't mind mistakes as it typically helps you learn a system or sometimes find a better solution to a problem you are working. (Again, with in reason. A mistake that takes down a major system is a no-no)
Own your mistakes, it will be better on your concise, better for your coworkers and better for the company you work for. In more frank terms don't be that guy or that a-hole 😀.