Reverse synergy?

Over the course of the past few years I have listened to several episodes of podcasts about terrible movies.  Unfortunately, I've found most of these explorations of this topic have been rather underwhelming and really aren't what I was hoping for.

These discussions tend to be rather superficial and just discuss aspects of the movie that didn't work/how they are bad.

What I keep hoping these these will be are real discussions of how experienced companies can have so many major multimillion dollar projects go so far off the rails. (One brief interview I heard about the making/meddling of Jaws 3 was quite enlightening.)  It would seem that in some instances some form of groupthink so overwhelms the process that reverse synergy (or synergy that brings out the worst features of a project rather than the best) dooms the project.

Of course, I suspect that one of the major problems - if not the major problem - is that anyone who could speak to these matters authoritatively could only do so at the risk of damaging their career in the industry.  Consequently the viewing public is left with Hollywood's true movie magic - no meaningful explanation of how experienced movie studios/makers allow themselves to regularly produce truly horrific duds for staggering sums of money.