Scenario: During pushback cabin crew tells you they can not arm 1 slide.
Have a look at the MEL? It will probably allow dispatch with one (or maybe more, depending on type) door u/s with no slide, possibly with some restrictions on how many pax are seated where. If the engineering action required is to write "door 1L stuck in manual" in the tech. log, then I'd be tempted to brief the CC/pax not to use 1L in an evacuation then carry on...