slides

Depends on the mechanicals. My steps are worm and sector gearing, if the motor or transmission fails, I either take a big step or disconnect them and move the step manually. My slideouts are both screw jack, so if a motor fails I can (very slowly) move the screw manually, wrench or crank. If a mechanical failure in the screw mechanism, I am SOL.

There are other ways of moving slideouts: hydraulic systems, cable pull systems, each with its economical advantages and technical limitations.

If you will obsess about possible failure modes, it might be more fit to your psychology to choose a RV that has no slideouts.