Cost and availability of developer time is much more of a factor in platform choice than a lot of people think, especially engineers who don't have to worry about the business end.

If you can find RoR developers, they are not cheap. If you're building a v1 product on a limited budget, and don't want to spend 80 hours per week writing it yourself, PHP is an excellent choice.

Having to read the code with a clothespin on your nose is a small price to pay.