Because it is very widely available for free and it is pretty great (good enough for most use cases) where the original solution (the c rand function) is awful.

Because it is very widely available for free and it is pretty great (good enough for most use cases) where the original solution (the c rand function) is awful. There might be better solutions but do they have about 20 good libraries ready to use for every language you can imagine? It’s a bit like qsort. It isn’t even the best but it is straightforward, widely available, free and magnitudes better than the naive bubble sort solution.