It's never happened to me but I've used non-reversible ratchet wrenches, the kind you flip over to reverse direction, in situations where there wasn't much clearance between the fastener and some other fixed object like a control arm or subframe, and if I backed out the fastener too far, there was the possibility that the ratchet would contact the fixed object and thus have no more room to move out, before the fastener came out, leading to an awkward situation where I could no longer tighten the fastener enough to remove the wrench, nor remove the fastener.
When I'm in such a situation I either don't use a non-reversible wrench, or remove it before it's too late and back off the fastener the rest of the way by hand or with an open end wrench. My only non-reversible wrench set are stubbies, and sometimes they're the only ones that work in a tight situation, but the very tightness of the situation is what makes using them potentially troublesome. On the other hand the lack of a reverse switch makes them somewhat more reliable as there's one less part that could break, and there's no chance of accidentally reversing direction with your finger, so they're nice to use in situations where this can't happen.
