My Experience as a Single Founder
So here is the kind of things you'll need to do as a single founder. For one, it helps to be a developer. Why, because without a product/service/website what else do you have to do. So first you develop. You build new features, you analyze, you build some more, you get some feedback, the cycle continues. People start signing up and using your product.
First, if you're lucky enough to have received some feedback from interested users pat yourself on the back for this one. If you develop something and no one's interested you don't have much else to do anyway so you're done. Next, as you develop some more you realize you need to start getting the word out about your service since everyone is giving you good feedback and they're telling their friends about you. But maybe you're not just getting the numbers you'd like to see yet. You'll most likely buy into the notion (as I did) that growth = success (and maybe that is right). You never know, your site could be the next best thing (you at least tell yourself this!).
So now empowered with users and interest you become a Marketer Guru. You'll want to learn just about everything you can about SEO (takes about an hour), then do as much as humanly possible to revamp your entire site to make sure you rank well at Google. You revamp alt tags, page descriptions, position keywords, create 'interesting' context....blah, blah, etc. You try Google Ads for a while, maybe Facebook, send bloggers emails, try to get some press, maybe even do some hardcore banner advertising. So now your traffic starts to grow even more, GREAT! Now you can relax, right? Well not so fast. Now you realize that the VPS just can't handle the new load you ingeniously placed on it, so you move to a dedicated server (thumbs up). You get that up and breathing, then you realize that you've got over 30Gigs of client files to transfer, a https cert to transfer, an SMTP server to configure, installing other useful tools, etc. So you stay up all night to configure the new server and pray that you'll get all your files transferred intact.
Not to mention you've got support emails filling in your inbox, you're getting automated exceptions in your email telling you that you're site is having connection issues with your SQL server and your hosting company can't tell you why, you have to figure out why your HELO is being rejected (ahem email), insure DNS is correctly setup, find out why half of Europe can't access your site but the rest of the world can. It goes on and on. I'm sure I forgot the half of it already. We have a product (magazine) as part of our site/service so optionally throw in creating a product.
So now we've got a few jobs for you: Senior Web Developer, Database Admin, Marketer, Publisher (in my case), System Admin, Help Desk ... and on and on and you start to get the picture. Oh and by the way you might have a day job too! So you'll be working just about every night from about 9-1am and probably half your weekends too. Let me tell you that lack of sleep catches up with you after a while, but I'm still amazed by how durable the human body is! And also, If you have a family, which I do, you'll need a very understanding wife.
This is more of a footnote but you could me suffering from a disease or mutation which allows your brain to solve lots of problems or generate a million ideas so you see opportunities everywhere which you'd love to start working on...but crap, you've got an inbox full support emails.
Good luck if you decide to go this route, but my opinion is get somebody to help you do something. One person can't do it all forever. Luckily I have a good support system which can also help. Knowing a few people here and there with different expertise can be of great value.
If you're interested, I am the creator of fotoblur.com and Fotoblur Magazine.