You can do a job by committee. Still, if one person can do it alone, you may prefer to have fewer cooks in the kitchen. NBA teams use the same principles.
Let’s take that metaphor literally. If you’re a master chef, you probably don’t want to work in a kitchen full of talented amateurs.
You’re capable of making the meal on your own, and it’ll be easier to do so.
If they’re weak at a particular position, they can have a platoon of players who play it. At the same time, they’d probably be better off with one solid starter.
The Los Angeles Clippers have a platoon at point guard. John Wall and Reggie Jackson are both solid, but neither are clearcut starters, either. If they wanted to, they could upgrade the position.
Here’s a deal that has them doing so by landing Mike Conley of the Utah Jazz.