1) Rome wasn't built in a day.
2) And if it's about commissions, which I think he didn't mention was the issue, you can just wing whatever if you're short on time as it's often the case. Actual commissions for compositions that I've had and others are always with "as much time as you need for it not to suck." Anything else is garbage since if it's about doing theory exercises why bother?
3) Everyone has their own pacing and sometimes things just take a while because polishing takes time. People should write things they are proud of, not just churn scraggy out because they need to meet a deadline (halfassed much?) I'm talking about actual composers, not people who do soundtracks or other thing where it's more OK to autopilot.
4) Artforms don't automatically have deadlines. Look at Gaudi's La Sagrada Familia, or many other examples where it took composers years to write a single work, etc etc. A painter can also take months and months to paint a single painting, specially if they have to start over and over because they aren't getting it "just right," then polishing takes more time.
5) Then there's the whole thing with "open" art, where the movie/piece/painting/etc is NEVER finished, and instead remains a work in progress during the entire life of the composer (Durufle's music was for example revised and polished over and over until he pretty much died.)
So shut the gently caress up, Tokke.