Is it better asking for forgiveness after the fact, than asking permission in the 1st place?

I am the type of guy that will ask permission or make sure it is alright before I go do something, use or take something belonging to someone else. Many I know ask me why I bother, just go do it and if someone makes a stink I can always beg forgiveness. If I suspect I would be told “no” if I asked then would that make any apology disingenuous? Isn’t to go ahead and do something because you don’t want to risk not being allowed is somewhat on the selfish side? I want so bad to do it that I would rationalize doing it at potentially any or great cost? If someone, your family or friends etc. did something like take something of yours without asking but simply said “I am sorry” when it got discovered or they fould you were not cool with it, how would you feel?