Probably because we're all so sign/logo oriented, we tend to believe our ideas, drawings and abilities can make or break a business.
There are many things go into the making of a successful company and the logo portion is only a small facet of the overall plan.
We all tend to tell our customers how much our signs, ideas and knowledge will benefit them, when actually, we're just trying to a make a 'Sale' based on our own past history. When creating a successful company, more than signs goes into the brew. Jingles, radio ads, uniforms, media action, television ads, computer/internet usage, newspapers and so many other forms it ain't even funny. To think some company has a better chance with yours' my or her ideas is just a small part of the puzzle. It's all part of your business plan..... or should be. Marketing and advertising are closely related and until you understand them both... you'll be needing help.
Other than the Red Cross or some place like the Golden Arches.... not too many things have a chance in this fast paced world anymore.
As with Dan, his company does mucho branding, but I'm sure, if it was known, the companies seeking his people out have already been established and going for one small piece of the puzzle with a name that's known and trusted. Successful people don't want to be doing this kinda stuff over and over until something might click.... they want the best, so they are willing to pay for someone known in the logo industry. So naturally, he's going to have a good success rate. Those people were successful coming in and now they're just better identified coming out.