Because it led us down a very fulfilling path of inventing interesting abstractions to solve problems, which tickled our mental fancy but led to bloated, sub-op

Because it led us down a very fulfilling path of inventing interesting abstractions to solve problems, which tickled our mental fancy but led to bloated, sub-optimal solutions. Unfortunately, it worked ... but eventually the bloat caused projects to hit a wall of unmaintainability. (If it had not worked so well in the medium-term, we would have moved past it much sooner). Another reason it derailed us is simply the level of buy-in it received from the entire industry. Everyone drank the cool-aid, so thought advancement in more powerful approaches -- such as functional programming, data structure-oriented programming and even data oriented programming -- was neglected.