Written by an inexperienced writer?

In an introduction that H.G. Wells wrote for The Time Machine thirty-five years later, Wells wrote that the story was obviously the work of an inexperienced writer. This was not obvious to me, although the structure of the story is a bit unusual. The story is quite short. The time traveller is not named. There's a first narrator who reports what the second narrator says, i.e. the time traveller himself. There is the main adventure, then another little mini-adventure at the end. The book combined scientific thought and social concerns of the time. It's unusual, but I can't see that it was written by someone inexperienced.