Obviously, TLG has a formula to assess ROI, and that is definitely the most important factor for them, but outside of that is there aspect that drives their decision one way or the other? 

 

Seems like sets withh IP face additional difficulty, there are still sets from 2015 that are “in review” (the office) 

Edited September 11, 20178 yr by Bat man

Profit, profit, and profit.

If they can price it high and still sell it like hotcakes, it's just printing money.

I'd also think ease of creation is a part of it. If they can make a set without creating new molds, that's got to be a perk on their end. Granted, if they want to maximize the time it takes the knockoffs to reproduce a set they should toss in as many new molds as possible to slow down their production time.

Edited September 12, 20178 yr by brickvoyeur

One important factor is to create something totally different to the already released (Ideas) sets:

Birds

Maze

Old Fishing House

Prate ship in the bottle

Another important factor is to create an existing spaceship/orbiter/rover/rocket:

Hayabusa

Mars Rover

Saturn V

Old not more allowed factor was to create sets from existing movies

DeLorean

Ecto-1

Dr. Who

Big Bang Theory 

 

Yet we get Women in Science and Research Institute?

There isn't one. It's a bit more nuanced. Recommend reading articles (can find some on brickset) where an AFOL evaluates each project in review.

 

 

14 minutes ago, Val-E said:

Yet we get Women in Science and Research Institute?

Those sets get them their progressive gold stars.