THAT's exactly the problem - it IS broken. STS is more than twice as expensive as Apollo/Saturn was, despite Apollo/Saturn being expendable. STS carries less than half the payload, was at best launched only about as frequently as Apollo/Saturn (remember, Apollo's man-rated flights only spanned 4 years: 1968-1972), and STS has killed an average of 1 astronaut per 7 flights. Counting Apollo 1, Apollo/Saturn killed 1 astronaut every 4 flights, but if you only count actual SPACEFLIGHTS, Apollo had 11 man-rated flights with no fatalities. This from a non-reusable program that was cheaper despite requiring 4x as many personnel.
Maybe a lot of that was due to the difference in NASA culture between 1960 and 1975 (when final design on the two systems was underway). No matter how you cut it, though, STS has serious issues - it never worked as advertised, the crew vehicle is in the path of shedding debris from other parts of the craft, mission objectives are not separated (crew SHOULD be separate from cargo - it's more economic. Cargo doesn't need life support and its associated weight), the list goes on and on. The design of the CEV addresses a number of those problems, and hopefully fixes it.