Getting to orbit was solved in the 1950s and 60s, and the only interesting problem left in spaceflight is making access to orbit dramatically cheaper.

The only interesting problem is dramatically reducing the cost of access to orbit, which is, if you can do that, you open up a bunch of new endeavors that lots of start-up companies everybody else can do. One of our missions is to be part of this industry and lower the cost to orbit, so that there can be a renaissance, a golden age of people doing all kinds of interesting things in space.