Client-facing lighting has different demands than personal creative work — reliability and repeatability across an entire shoot often matter more than one striking frame.
On-location work requires adapting to whatever light exists at a venue; studio work offers full control at the cost of upfront setup. Many professionals maintain competence in both, since client venues and preferences vary.
Consistency across a session — many similar shots in sequence (formal portraits, headshot sessions) — matters more than any single frame being exceptional. A slightly-less-perfect but highly consistent setup usually serves a delivery better than chasing the ideal frame-by-frame.
Developing a small set of reliable, repeatable setups (a go-to one-light portrait setup, a go-to two-light headshot setup) reduces both setup time and the risk of inconsistent results across a delivery — and practicing them until they're fast and second-nature is what separates comfortable professional execution from slow, technically-correct amateur execution.