Reference:
viewtopic.php?p=174972#p174972Conditions for stopping / interrupting attacking are in Fighting Fundamentals, p. 138:
"[...]
- Any continued attack helps the defender more than the attacker.
- [...] immediate attacks [...] are neither available nor profitable.
- [...] gains can be made, but it is still unclear which is the best. [...]
- A different fight is more urgent."
Also see other parts of the book, such as p. 219+. In particular, implicit assessment for the last cited point is explained there.