Apart of not knowing / unable to start from scratch, this is about frequent, and infrequent use. The latter also means not-that-important-in-overall-landscape, and brings forgetting and perceiving it as less "ROI", so one (hopefuly) finds and copy-pastes that-last-working thing into.. whatever Frankenstein.
https://utcc.utoronto.ca/~cks/space/blog/programming/Frequen...