Try this
- Choose a time or natural checkpoint for deciding whether to continue.
- Agree on how to leave the task in a usable state if stopping. Keep additional work a fresh choice rather than an automatic extension because some remains.
A worked example
“After an hour, let’s decide whether to continue or leave the rest.”
An invented example to adapt, not a real exchange or a script you have to follow.
Before you leave it here
Stopping at the agreed point is not abandoning the other person.