From my experience, bad theatre usually stems from one of two things: either an overabundance or extreme absence of fear.
On the one hand, when a company takes reckless and unsupported liberties with a play, their fearlessness and complete abandon produces theatre that is wayward, lacking purpose and direction. The audience leaves feeling confused and attacked, not by the story but rather the presentation of the play.
On the other hand, when a company of actors is afraid of the urgency or immediacy of a play's content and impact, the result is an artistic paralysis that prevents the ensemble from being available to adventurous theatrical exploration. The show becomes half-hearted, flat, and monochromatic.
It's a difficult balance to navigate.
Of the two, I must say I prefer the former. Shows approach with this perspective at least have a level of investment and engagement that keeps them somewhat entertaining. What I saw yesterday more resembled the latter, which is far, FAR more depressing.