This guy just reinvented men's underwear

Don't quit your day job ... yet. Or, at least wait until you talk to Carol Roth, a small-business advocate, "recovering" investment banker, and author of "The Entrepreneur Equation." In a new digital series, Roth takes on would-be entrepreneurs who want to abandon their careers for new small-business ideas. Here, she analyzes Garrett Ryan, an advertising executive who reinvented men's underwear with his start-up, Mr. + Muse. Here's Carol's advice.

Have you ever thought to yourself, "I wish they would re-invent underwear?" Maybe not, but that's exactly what advertising executive Garrett Ryan did. And he was so entranced by the idea, he left his six-figure advertising gig behind to create Mr + Muse, a gifting company that targets women to send hip skivvies to the love (or loves) in their lives.

He's hoping that there's an entrepreneurship gene in his family, as his brother is the serial entrepreneur behind Method Soap and OLLY vitamins.

I had to question the premise of getting women to buy underwear for men for special occasions as a business model, especially since, for most women, if the man's underwear is clean, that in and of itself is a victory. Plus, while the underwear is cute, it's obviously meant for men who are in very good shape, which is a small fraction of the population — and even less of the married population!

Moreover, by making underwear a gift, Mr + Muse is trying to take a staple that people buy in multiples and change that into a gifting occasion. Even if someone were to buy undies as a gift, the business is missing out on the holy grail, which is repeat purchases. If he's going to spend heavily to acquire customers, he wants them to buy over and over again. The positioning does not encourage this, which is a major model flaw.

Also, Mr + Muse targets women — you can see this in everything from its creation story to the brand name. This means that the brand is ignoring a big potential customer base which is the gay community. And if there's anyone who is going to care about their man looking hot in undies — especially ones that look like these — dude, it's another dude!

Normally, I would tell Garrett not to quit his day job … yet. However, he's already taken the plunge, so we have to figure out a way to make this work.

I encourage him to rework the brand and the purchasing so that it easily engenders repeat purchases if a recipient loves the undies. He also needs to figure out a way to make the brand gay-friendly, because not only is it a substantial and appropriate market, it is easier to target from a marketing perspective.

If they throw in some cheeky marketing (pun intended) and perhaps even consider doing a fun cross promotion with someone who has an installed user base like a Tinder or a Match.com, that will better position the brand to succeed.



If you're an entrepreneur looking to turn your hobby or "jobbie" into a full-time career, we want to hear from you. Email: AskCarolRoth@cnbc.com.