[naasking]

> I became increasingly terrified of making changes.

That's the main value of automated tests.

[TehShrike]

I rarely feel like tests make it easier for me to make changes later. Types do give me that feeling pretty reliably, though.

[naasking]

Agreed that types are better, but good test suites contain plenty of reminders of corner cases that you probably forgot to consider during your refactor.