[tomrod]

Any inights why the performance often varies between a Model T Ford and a glacial boulder?

[michaelt]

I mean, presumably it's subject to the two curses of modern software:-

1. Unless major customers are actively closing their accounts due to the poor performance, improving performance isn't a priority.

2. The people who pay for it aren't the people who use it, so the performance can get very, very bad before customers start closing their accounts.