What's the risk in building a company to solve your own problem?

As others previously mentioned, this question is rather unclear, so I will be addressing the one in the title.

The biggest risks you take on are...

1. Time investment. Time is a big deal, and building a product that solves a problem takes a significant chunk of time. Consider first if the problem is worth this (biggest, imo) risk.
2. Financial investment. Nowadays, with the democratization of tech, this is not a big issue - however, it depends on the problem you're trying to solve.
3. Emotional investment. Be prepared to invest emotionally on something and the possibility of either success or failure. This is a hidden investment many don't realize when making a product, and it's much better if you realize that you are invested rather than finding out later.

I don't understand your question entirely. I don't know what Rhizata is either.

But nevertheless, I will answer with my opinion on the fundamental question in the title.

I believe that solving your own problem is one of the best approaches to starting a business.

1. It makes you more passionate about the problem and the solution.

2. It provides you with a drive you may not otherwise have.

3. It gives you an insight in to the mindset of your target market immediately, as you are part of that audience!