A team will argue. One man will not.
One person can’t be good at everything, we are admonished, typically by people who don’t want to work that hard. Bollocks, I say. One person can be good at everything. Not at the same time, of course, and I doubt that one person can be really superb at everything.
Here is the crux: When a project is wholly controlled by one person who doesn’t answer to anyone else, that person will do everything he thinks important, and only what he thinks important.
He wouldn’t undertake such a project without a clearly perceived need and a clearly conceived answer to that need. As with commissioned development, there may be several project reboots and re-conceptions. Prototyping clarifies perceptions and reveals technical limitations.
Eventually, he will be satisfied and will reveal a work with such coherence of design and execution that bureaucracy cannot hope to compete.
A problem here is that we live and learn. Throughout the project he refines his technique, and the quality of work improves. This is a strong argument for sticking with what you know in development.
Sometimes, our virtuoso will look at his handiwork, and see this in it. And do it again, from scratch, but very quickly. And then we get a cut diamond.
Why do I keep saying “he, his ” rather than “he/she, his/her” or the grammatically grotesque “they, their”? Because, like music, only men create great software. If you disagree you have only to point me in the direction of just one virtuoso software development by a woman, and if Google knows about it I will make a correction and a commitment. In the meantime, I assert that “he” is factually correct.
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As ever, Scott Adams tells a home truth in the guise of humour:

The person I’m thinking of is not stupid and this has made me wonder how anyone can vacillate between being intelligent and, as Adams puts it, failing the Turing test. The conclusion I have reached is that this happens when people are well out of their sphere of expertise - so far out of it that they don’t even know the extent of their ignorance. I’ve noticed that under these conditions, people resort to aphorisms and herd behaviour.
Not long after this thought crystallised, it came to me that this is very likely a standard fallback behaviour, not just for primates, but for any animal that could remotely be described as intelligent.
This observation is very interesting in the context of my existing notions on the nature of intelligence. I’ve always defined intelligence as the capacity for analysis in the absence of precedent. More recently I have wondered how to factor in the inclination to analyse.
The capacity for intelligence is (IMHO) intrinsic to any large layered neural network with feedback channels. However, this is true only to the extent that the potential for huge bulging muscles is inherent in every man. Couch potatoes utterly fail to bulge, except possibly around the middle.
Regular exercise is required to procure even slight bulging. Or cerebration.
Gym junkies like working out.
Intelligent people enjoy analysing things. I say “analysing things” rather than “thinking” because you can think about doughnuts, boobs and beer with very little in the way of analysis.
The application of intelligence is an inherently time-consuming activity. Mammals invented dreaming as a way to cope with the fact that you can’t do a thorough analysis while something is trying to eat you.
When decisions must be made under fire, it greatly helps to have thought the situation through in advance. When this is not possible, due to unforeseen circumstances, it becomes necessary to fall back on more general precedent. This is no more or less than the adaptation of solutions to similar problems on the basis that they worked and have already been thought through.
When there is no precedent, behaviour is erratic and unpredictable. This is itself a survival behaviour: the unpredictability of one’s confusion can throw a spanner in the other party’s works.