I've dabbled for years with creating on my computer. I even won a few contests--though I quit competing when I heard it takes jobs away from bona fide graphic designers. It was probably around that same time that I slowed to only occasional design tinkering (for my own use) and fell behind in keeping up to date with learning how to use new software tools.
I haven't stopped being critical of other's design work, however. Now that I spend more time on Facebook reading restaurant updates, there are too many opportunities to see owner created logos or icons. It's not a good trend, in my opinion.
If you're putting all you have into running or starting up a business, a logo is an important investment. It should be clean, crisp and appealing. It should be suitable for using in a variety of situations--not just a sign. Format is important, too. When you head to the printers, it needs to be ready for them to do whatever it is you've asked them to do. Otherwise, they'll need to spend hours trying to recreate what you've already spent valuable hours working on. Are you starting to get the idea?
Plus, they already know what will and won't work for all the situations logos are put to use. Not to mention all of the benefits of fonts, kerning, use of color and how to get a design to communicate your message. Because, face it, you DO have a message. Whether it's to welcome customers, encourage them to step through your doors, whet their appetite or give them the impression that you know what the hell you're doing.
Looking like a professional. Now that's a great idea.