And I have been forced to write sorting algorithms from scratch as well. But it was truly a last resort. In my case I had to work with data that literally did not fit in uncompressed form on the computer that I had to work with. So I had to write a disk sort where data as kept in compressed form. (I used merge sort for this.)

However the fact that sometimes we are forced to our last resort doesn't change the fact that we should be aware that it really is a last resort.