[guenthert]

FORTH (indirect threaded implementations at least) allows to redefine words while the system is running (fingers crossed).

Just because that feature is available and at one time was desirable (when machines were so slow, that compiling would break the flow), doesn't mean one needs to or should use it today.

[Volt]

Compiling can certainly still break the flow depending on the language and size of the project. Just ask Google.