Some are "Seed" base meaning if you attempt it x times in that percent it will eventually open, for example the chance is 50% but you will need to try to open it at least 3 times for it actually open since it was "Seed" to fail on the first 2 attempts first then on the 3rd attempt it will 100% open. Even how many tries you do to save scum for first attempt it won't happen until you reach the expected attempts to actually open the door. It like how crane machines works that's the short version if you don't know how that works just think of it like you need to drop 500$ worth of arcade coins for the crane claws to grip the object tightly.
TLDR: If you want to make your life easier just go for DEX 30 you will open 98% of everything in the game.
But the thing is the the door actually opened before I reloaded.
I paid the money, went to the part of the town with the gate and BAM, it was instantly open.
So I reloaded to the point before I got cought by the guy on the street, went up again, into the sewers, saved and tried to open the door again, but it never opened, no matter how many times I tried.
So there should be something that changes this seed, or values of it.