Even the best greens keepers are bound by the weather. When to put down fertilizer and pesticides, when to aerate greens and tee boxes. When to aerate the fairways, which needs to be done every so often.
They need some good luck. And let's face it - as our climate becomes more and more unpredictable, as it has over the past 10-15 years, their jobs become even more complicated. Hell - half the time - even our most educated meteorologists can't accurately predict the weather. And weather is a huge, huge part of how the better greens keepers schedule their maintenance.
My club was scheduled to aerate three weeks ago. Well... we had snow a few days prior to them doing the greens. So now the greens keeper is having to work around that. Then we had pouring rain the next two days, followed by high winds and more rain the days following.
Agronomics and science are certainly involved, but the quality of work by the maintenance staff is pretty much governed by what Mother Nature allows.