«...a sound reason...»

Sure. Consider this true story: Once upon a time a young C programmer needed a little script. In his hubris - a real Dr Wisenheimer - he wrote it in an obsolete Perl 4 style. Everything self made. No libs etc. Some years later a bash programmer (a real Perl hater) inherited the script. At this point the little script was already swollen to a monster of many hundred lines of code. The basher left the company and a real Java fan boy inherited it. He added tons of features and libs. Now this whole crap is by far > 1000 lines and really stinks. It is mission-critical. If it fails: Airplanes grounded, 100 printers down, VPNs broken, monitoring runs amok, what ever desaster you can imagine. And a poor 24/7 admin needed to restart the stuff every time it crashed. Sure, this is prose. A short summary of my experience. The statement is: Sometimes it’s better to make a hard break. Who will be killed if such crap fails? The poor guy which inherited it. And: If you want to maintain or extend such stuff you need to understand it’s logic. BTW, my second project ever was a complete rewrite of the crap I wrote in my first project. After I «discovered» how it really should be done.

Best regards, Karl