A friend has been feeding my wife and I the "Thin Man" series of 1930's-40's films. We're through 3 now. And, as with almost every other "Serial" attempt, they don't get better.

It used to boggle me, this phenomenon within the movie industry, but I think the key to the answer is "Industry".

When any art form is explored in depth, whether you call them "sequels" or a "thesis", it is NOT the most difficult aspect of that research. To KNOW what you're doing, and to determine the most innovative, positive aspects, does not require the most time. And, each work should, at least in theory, be an equally positive exploration or an improvement on every level. (Technique, formalism, invention, personal/cultural/era expression, etc.) What requires the MOST time is finding NEW territory for your exploration in the first place. THAT'S hard.

Why is it most MOVIES serials seem to flounder and fail to validly explore the initial ideas?

Industry. The influence of Profit and Loss. "This first movie was successful. Let's dissect it - not for its best components, but for its people-pleaser bits. We know people don't like to be challenged, we know they like to feel secure, so the "pleaser bits" are to be repeated even if it makes the film worse. We'll take the money, and, when "bits" stop working (the secure become bored), RUN !!"

It's not about Art. It's about Indu$try. Fa$hion.

So, this is why I'm most attracted to independent film making artists - they run (or ran) the show, so to speak. There's a Boss. A Controller. A Tyrant. Someone with a vision. Someone who can't be shoved around.