One thing I've learned along the way is: Don't listen to "advice" from failures. People who have only failed will do you nothing good because they don't know why they failed (at least until they keep trying and eventually manage to succeed). They think they do, but they don't. It's like asking people of the ancient world if the earth is round. Their reality doesn't include a rounded earth, so they will of course say it's flat, and they would be 100% confident that they're right.
Also even the people who succeeded don't really know why they succeeded. In fact, the more successful they are the more clear they will be about the fact that they don't know how they succeeded. They will say something along the lines of "we succeeded because of luck and persistence and sometimes a bit of clever ideas". If you don't believe me just find someone successful and ask that question, if you can.
"I failed because my site wasn't an SPA" was the stupidest thing I've ever heard. It's nothing more than a backward rationalization to make himself feel better so that he can deny the fact that he was simply incompetent in many aspects. That's why you don't take advice from these people.