I think we won this game because after half time, we pressed and pinned West Ham back in their own half from the 45th minute to when we scored. Usually, or at least last year, we were only doing this when we were trailing or if we were drawing at around the 70th minute. In the end, they got tired and eventually conceded. This is what United do successfully to teams. Constant pressure.
Whilst we should be disappointed with the defending (we shouldn't have to score 3 goals to beat West Ham), we should be pleased with our spirit. We kept on pressing and going forward with belief that the goal would eventually come. Encouraging signs. Now we just need to tighten up and go on a winning streak.