Well, they didn't try very hard to make things right. Users revolted, so they caved. That's all there is to it. The "unfortunately these people are most vocal" misses the mark completely -- had they been NOT vocal they would've faced enormous bills or they would have to spend 50 hours trying to migrate to a new system. That's if the data can be exported and imported freely, which is rarely the case.

So the customers spent hours comparing the offers of the competition, all the time being frustrated because this jumped on them from nowhere. And then, 2 days later, they hear "Whoops, my bad!". That just doesn't fix the damage, now does it?

If a thousand customers each spend 3 hours worrying about what to do, and these numbers are conservative, then you've created 3000 hours of unnecessary frustration. So the damage will exceed $300.000. Just with one ill considered move!

Whoops, sorry!