When PCs were first designed, little thought was given to the likelihood that their owners would need to open them up, to change boards or jumper wires. The first PCs were hard to open, sometimes requiring uncommon screwdrivers. But as PC sales increased, vendors got smart about case design. Within a few years, there were cases that could be opened with nothing more unusual than a quarter, or with clever fingers alone.
Right now, I'm working with a PC that requires me to unscrew fourteen screws to remove its cover. Fourteen! I wish I could talk to the person who designed this case. The way I see it, surely thirteen screws would have been enough. Don't you agree?