If you make a mistake you should fix it
Chuck borrowed Tim's lawnmower and broke the blade.
Chuck wants to mow his lawn.
Chuck gets a new blade for the mower and returns it after he finishes mowing.
Chuck give the mower back, with the broken blade, and borrows someone else's mower to finish the lawn.
Tim is grateful and lets him borrow other items from time to time.
Tim never lets Chuck borrow anything again, and the relationship is strained.