There’s a fundamental difference between teams working on new game conceptualization and teams focused on production and updates. The first kind works more like a rock band; the latter, like a sports team.
To conceptualize new games, you need people capable of genuinely wrestling with an idea for a sufficient amount of time. You need people who help each other and cover each other’s limitations. These are people willing to find new formulas and to create art.
Once you have it—once you have the formula—you need the resilience and technique to produce it. This is where you need top talent; you can’t afford to lose time and compromise the whole team.
Both types of talent are hard to find, but selection processes only spot (and often badly) the latter group: the sports team. That’s why people like me, the rockers, are sometimes needed.