Which TV show plot would fall apart if the main characters were a bit more decisive?

Monk. Absolutely Monk 

Lucifer. Had to stop watching where the major driving source of conflict is poor communication and decision making between the two main and all characters really. It’s a good show but could be so much better

Nearly every plot point of The 100 is invalidated if any 2 people actually spoke to each other

Most of them. There would be no more will they won’t they that drives romantic drama and sitcoms. Chuck off the top of my head would be dead in the water. Even if it gets past the first episode.

AHS Murder House. If the Harmons just left the house after the first wave of extremely obvious haunting, the entire series ends immediately.

Silicon Valley. Richard's waffling was so annoying, but it did drive a lot of the plot.

Oh, ‘Gilmore Girls’ is a great example. I guess the classic “will-they-or-won’t-they” of Mulder & Scully from ‘The X-Files’ would fall apart if they had gotten together sooner: From episode 1 they clearly had a chemistry together, but had they consummated that there’d be so many stories we as the audience would’ve missed out on.

Every soap opera ever made and procedurals like Doc, The Resident and Grey's Anatomy, Chicago Fire, Chicago Med, Station 19 are pretty bad in this respect, they argue for episodes over nothing.

Um life in general

The Big Bang Theory

Silicon Valley

Breaking bad

Like most plot points and characters in Game of Thrones.