Actually, Symfony seems like some kids went to basic OO design courses and took everything there seriously. It also causes the end product to be measurably the slowest in the world. http://www.techempower.com/benchmarks/

I think this is the worst symptom: Sure, you can write snappy code that performs fast but when you try to reach a higher abstraction level, all those fundamental design failures catch up and make everything awkward and just bad.