How useful are type "a" people at all? Sounds like a kind definition of people lacking passion and the desire to grow. Isn't hiring them a recipe for mediocrity at any stage?
Some positions can't involve non-a people. You couldn't hire someone with world-conquering drive to be your 1000th recruiter at Podunksville University, Delaware.
I don't know about that. I'm perhaps a bit unrepresentative since my normal job is also at a (later-stage, profitable) startup, but I found my day job is far more stressful than the startup.
When you work for someone else, there are a large number of factors that you cannot control. You can't pick your technologies: you generally have to go along with what the rest of the team is already using. You can't pick your company culture: it's already been established. You can't pick your market (okay, you can't really either with your own startup). You're stuck with the existing codebase.
All this is fine if you also pick up your employer's values and expectations. But I don't know any startup founder that's like this. Usually, if you're interested in starting a company, it's because you have some internal standards for the quality that you'd like your code to live up to and the ease with which users can use it. So if you're working for someone else, you can easily get stuck with your own standards and your employer's tools, and the two may not match.
This is really, really stressful.
When I'm working on my startup, at least I know that any problems I'm having are my fault. And I can fix them. If I don't like the quality of the code I'm putting out, I can make the call to postpone feature X and fix bug Y instead. If I find that a framework is becoming more of a hassle than a help, I can rip it out and replace it with my own code without my boss vetoing it.
There's a whole other level of stress that comes from mixing both day job and startup. Right now, the most stressful thing in my life is wondering whether I should quit the day job to work full time on the startup. It's stressful because there is pitiably little information and yet it's an incredibly important decision. I won't know whether the reduced time available has caused me to miss my market opportunity until I've actually missed the market opportunity, at which point it's too late. Similarly, I won't know whether the added time pressure has made me mortgage the startup's codebase until it becomes impossible to work with, at which point it's generally too late to fix.
(b) For the earliest employees, it's more like being a founder than having a normal job.