Yes. I am not even joking. Facebook was so terrible that they had to literally reinvent their wheels (hiphop). Its not hard to become a large company when you have black budget backing as confirmed by Snowden.
You don't think its strange that facebook hired PHP programmers to create the product and then have to hire competent people to fix that shit as far removed from company logic as possible?
I hope you are joking. Those people you call incompetent built arguably the best web application in the world propelling itself into a global corporate juggernaut and that qualifies as built by incompetent people?