Do these comments surprise you? They shouldn't. As authors, we have to realize that the more we write, the better we get. When we're writing our first novel, our first story, and, yes, even our first sit-com, we don't see the flaws. We think it is good, maybe brilliant. But when we look back on our earlier work, we can see that it is rough and it has flaws. The later episodes of Seinfled are much better than the first couple of seasons. One of the reasons for this is that the writing got better. David and Seinfeld began to understand what worked and what didn't--even if they didn't realize that at the time.
I often have to keep in mind that writing is not just an art; it's a process. Most authors work for many years before they get published--and that's probably a good thing. We want people to read our best stuff--not our early attempts that feel like high school plays.