Pragmatic Decisions
There is code I wrote that has been working apparently correctly for years, but looking at it now I'm frankly horrified by it. Were modifications now needed and I was to work on this again, to do the job 'properly' would require a major re-write. However, if I apply patches with extreme caution, and very very thoroughly test everything, it is likely to carry on working - apparently correctly - for many more years.
I haven't (yet) had to make such a decision.