Basically, if you accept that your first 10 games will suck, and you don't try to make your first game fantastic, then your first 10 games will suck. Worse, you might get good at developing sucky games. For most developers, not just game developers, it's likely that their first some number of projects will suck.
I always thought that the mantra about your first 10 games will suck was a way to take the pressure off you and get you to develop a game. The problem is that we psych ourselves out; we don't develop anything because we're too fearful about making a bad game, and we procrastinate, and we hem and haw and never develop anything.
It's not so much that it should suck, as much as that it probably will suck, just because you don't know what you're doing yet. So as you said, it's just to set your expectations right, not your ambition.
And this is where I deeply agree with the author, and why I don't spend as much time reading articles as I once did: All of this is advice is probably right, in context. In the incredibly rich and impossible-to-convey context of the author's situation. Used outside of that context, it could be exactly the wrong advice.
It's like Soeren Kierkegaard said, you can't pass experience on through writing, it has to be lived.
also, not sucking and financial success are two different things. You can be a financial success with a game that sucks. Getting to where you're consistently making good, innovative stuff really does come sometime after your 10th game.
I always thought that the mantra about your first 10 games will suck was a way to take the pressure off you and get you to develop a game. The problem is that we psych ourselves out; we don't develop anything because we're too fearful about making a bad game, and we procrastinate, and we hem and haw and never develop anything.