TV serial ratings are meaningless

TV Serial ratings don't make sense. Lets compare it to the movies. If a movie is rated higher, suppose, by a small bunch of people, many people can choose to watch it and rate their opinions about that movie. So, over a period of time ratings normalise. But in case of TV serials, one cannot easily do the same as TV serials are too lengthy and time consuming compared to movies. If one does watch some episodes and looses interest, his ratings are not genuine as they are only given based on the first few episodes.
Many TV serials and their seasons improve drastically mid-way.
I am talking abt one season here. Many TV serials have multiple seasons and all that has just one rating page. Its totally ridiculous. Now, I have seen that Imdb has created 'Top Rated TV Shows' just in line with the movies. I don't think this is a good idea. TV show ratings(if that show is very lengthy compared to a standard movie) should be discredited and removed, but on the contrary Imdb is promoting this idea of TV show ratings.
I once undid all my TV show ratings, just because principally I found it senseless and meaningless.