Serious question: as a user (not as a developer!), have you ever seen substantial improvement in a piece of a software from a ground-up rewrite?

In other words, have you ever used (but not co-developed) something where the developer(s) decided on stopping evolutionary work and instead embarked on a substantial rewrite, and the outcome as you saw it firsthand was a real improvement?

If so, please state your example. Please stick to personal experience, rather than hearsay. Thanks!

@xahteiwi
The details are confidential, but i have had 3 (large) converisons conversion projects over my career and the reactions are as followed:
1: "finally we do not have to click through 8 menus to finish"
2: "wow,it does not take 50 seconds to load, but <2" (real measurement)
3: without the conversion, we could no% have processed those documents at all (sheer complexity of the data has grown over time, almost impossiblento calculate by hand anymore)