The reason you don't want to get stuck is because there is parallelism: between the other computers on the network and your computer, or between the between th

The reason you don't want to get stuck is because there is parallelism: between the other computers on the network and your computer, or between the between the person using the computer and your program. (this isn't really different than a disk or a network doing things in parallel with your program, only in this instance the other thing runs on flesh instead of on silicon). If the disk couldn't do things in parallel with your CPU there would be no point in avoiding to get stuck for too long in your main loop, since either one would have to wait for the other anyway.