When what you're doing is simple but error prone, or not well defined fast feedback can make you much more efficient. If you're using an underdocumented API/dataset, the best way to understand it is to probe it with code, quickly iterating.
I used to write a lot of LaTeX and make lots of simple mistakes (missing backslashes typically). I found having an environment where I found my mistakes as soon as I made them more efficient than searching through the output for all mistakes, and then for each mistake finding the corresponding source and correcting them.