First, I had to come up with cash to pay someone. A painful thing to do when you're bootstrapping with no real income.
Second, I had to spend copious amounts of time not only writing a technical spec for someone who didn't grok the app but also carefully crafting a contract that would assure that I kept the IP.
Third, maintenance has been a bitch. Iterations take weeks instead of days, and I'm never a contractor's top priority.
In contrast, my partners are (like me) working for equity, have a deep, intuitive grasp of the product and what it does, and are engaged enough to not only turn around changes quickly, but also suggest improvements themselves.
Obviously, there are situations where renting a coder will be one's only option. My experience has been that it's an awkward, painful process.
In the future, I would choose to cobble together a non-functional prototype (I'm a UX designer who writes display layer markup) to help me attract a technical co-founder or an investor rather than hire another contractor.
An analogy is that you don't have to learn everything about cars if you are just driving to your day job. Let a mechanic take care of that, and you can focus on what you do best. If you want to be a NASCAR driver, you should know everything your pit crew knows.
To think that you can contract a coder and get a company back is fairly naive.