It’s nothing to do with the Coalition, it’s to do with PNC behavior and actions.

The PPP itself is a rainbow coalition, put together by the bungling APNU/AFC Coalition. 

As you said Coalition don't last so can the PPP rainbow coalition.  The PPP couldn't win without the CIVIC, Amerinds and the Douglas.

Let's examine Guyana's population. DJ can't warp his head around this:

Indos 40 percent

Afros 29 percent

Mixed 20 percent

Amerind 10 percent

Others 1 percent

39 Percent of Indos ( I and referencing as a total percentage of the population) voted PPP, 9 Percent Amerinds voted PPP another 4 percent of Afros/Mixed voted PPP. It proves that it is highly unlikely that PNC will ever govern again unless the PPP messes up big time. Shuman failed to attract Amerinds so he has no other choice but to join the PPP.

Depressing news for PNC supporters. AFC is now dead meat with ZERO chance for revival, only Mitwah, Ramjattan and Moses are left.

The face of the PNC in parliament was 90 percent Afros despite the fact that they represent only 29 percent of the population. No wonder they lost.

PNC underestimated the AFC and Granger abused and destroyed them but in the end he ended up destroying the PNC. He cut his nose and spoilt his face.