honeywellsims4news:

KOTAKU: ADDING POOLS TO SIMS 4 ISN’T EASY, CLAIMS EA
Interview with Graham Nardone

GRAHAM NARDONE

“It’s easy to look at something and think, ‘That looks pretty simple.’ When you think about a feature like pools upfront, it looks like a square box on the ground and you put a shader on the top surface and have Sims jump in.”

“But ultimately, it’s more complexity in terms of what tech’s there and what isn’t there, what we have to build to support this. How do we cut down into the terrain, how do we get Sims going through portals across different levels of pools? There’s so much that’s going on in the background that you don’t end up seeing just to have a Sim go swimming.” —Graham Nardone

“It’s not a matter of it not being important to us or our focus not being in the right place. As we chat with fans and they continue to inform us of what they want, they’re obviously interested in pools and toddlers. They want those in the game. So we’ll continue to listen to feedback, something we’ve always done with The Sims.” —Graham Nardone

And

“I’d really just say look at what we’ve done in the past. We’ve had a variety of different ways we’ve delivered content to players, and I think we’ll continue to support what they’re looking for.” —Graham Nardone

All of the statements from Graham are above but you’ll want to go read the full article, Adding Pools to Sims 4 Isn’t Easy, Claim EA. 

Note:  The article references the Glassbox game engine that Sim City uses but Graham Nardone has stated more than once that the engine for The Sims 4 is completely new.  source