I once worked at a company that had a successful product ($40M in sales, $15M in arr via support plans). They did a rewrite, that of course went a year long and was poorly handled by sales and marketing ie it was talked about freely with customers and prospects; contributed to sales drying up while they all waited for the new hotness.

I knew the rewrite was going take a lot longer than they were saying, both due to common sense and because there were conflicting goals from ceo and cto.

I went to the ceo and made a case for a back up plan, myself and a few others could continue on the old busted version; bug fixes and minimal enhancements only, insurance if you will. I really thought about buying it but had no way to finance anything like that. CEO didn’t bite and was in process of selling the company to a PE firm.

I left when the new version finally shipped with half the features and twice the bugs. The PE installed CEO wrecked the sales org and sales never recovered.

As a side note, a foreign firm had pirated a much older version 10 years prior, rebranded and was #3 with it in that market.