I was once a wannabe entrepreneur. Fresh out of college and a summer internship at a VC firm, I thought I knew what I was doing. Though this was 2000, and all startup & VC blogs we've grown to love didn't exist yet, I did have mentors available. I should have leaned on them a lot more, but I didn't, or at least not in the right ways.
But all the ways I've failed, and there are certainly many, is not the point. I just want to let you know that I've been there, and that I hope the rest of this post doesn't come off as annoyingly condescending.
Since 2000, I've been doing and thinking about startups constantly. Even though I'm an introvert, I end up meeting or otherwise crossing paths with a lot of entrepreneurs. Unfortunately, I'd classify a lot of them as wannabes.
What follows are some symptoms I've seen over and over that usually (though not always) indicate a wannabe entrepreneur. If any of these describe you (or someone you know), I'd take it as a sign to step back and think hard about what you're doing (or have that conversation with your friend).
There are cures. Usually it means what you (or they) are working on now will fail. But perhaps it is salvageable with a few tweaks or a change in direction. And if you/they are really in it for the long term (as real entrepreneurs are), then there will be other startups.
Symptom: a year has gone by and you have nothing to show for it.
Cure: get stuff done. That's what real startup founders do. Customers don't care about excuses.
Symptom: you haven't really talked to any real customers/users.
Cure: read Steve Blank's book. Get out of the building. "No plan survives first contact with customers." A related (non-wannabe but first-timer problem) is confusing the user with the customer. I did this on my first startup, and it was one of my primary problems.
Symptom: you're going around calling yourself a CEO.
Cure: you're a founder. You're not powerful. No one cares about what you're doing...yet.
Symptom: you aren't knowledgeable about startups, especially your own space.
Cure: read stuff & regularly talk with the smartest startup people you know. At the very least, you should know the whole history of your space--failures, acquisitions, IPOs, reasons for such, etc.
Symptom: you just need 10-25K in investment.
Cure: get your own 10-25K. Do consulting. Maybe convince friends and family. If you can't raise that much from yourself and your existing circle, you aren't going to be able to raise more from strangers. I did consulting for a few years, max 4hr a day, so I could focus the rest of time on my startups.
Symptom: you have spent months researching the right architecture to build your site.
Cure: build it already. You seem like someone more interested in technology than startups.
Symptom: you don't understand your startup's assumptions.
Cure: make a spreadsheet and try to predict the key metrics of your business. Yes, the financial projections that come out of the spreadsheet are probably worthless (or grossly inaccurate), but not their underlying assumptions. Those are the things you need to prove and the first step is knowing what they are. As a side note, this exercise will help you understand how much money you need to raise, if any.
Symptom: you've written more than a 5pg business plan (intended for others).
Cure: spend that time talking to real customers or building your product. If you think it will help you understand your business, build a spreadsheet with assumptions instead. If you think investors will read it, know that they won't. Note: I have no problem with people analyzing their businesses internally through brief writing; I do that too.
Symptom: you now just need a programmer to code up your site.
Cure: either convince a real tech co-founder to join you, or learn how to code yourself. It's not that hard, and if you think of startups as a career, it's a great skill to have even if you just manage tech people. You don't have to major in CS in college to be a programmer, e.g. I was a Physics major.