A few rhetorical questions:
Is a physical therapist with a professional logo better than one with a handmade sign?
Are you more likely to stay at a hotel that you've heard of as opposed to an unknown one, even if 'heard of' refers to the fact that they've run ads?
Do you believe that companies that rank higher in search results are better than the ones a few pages later? And if you don't, then what's the reason we so often stop clicking after one page?
There are more ways than ever to spread the word about your work, but we live in a culture where paid ads still have clout.
"As Seen on TV" was such a powerful phrase that companies brag about it, right on the box. And that connection between paying for attention and quality still remains.
Over time, we've been sufficiently seduced by marketers that spend on the surface stuff that cognitive dissonance has persuaded us that we must be making those choices for a reason.
Find the discipline to build your projects like you won't be able to run ads to make them succeed. A product that sells itself, that's remarkable, that spreads.
Then consider running ads as if you don't need them.