[CrowKenobi]

Originally Posted by Pop-Punk Sucks

What a lot of people are forgetting (In terms of why American shows last sooo long as opposed to animes that are very short) is that the purpose for Entertainment is money, and that's it. Until nobody watches it, 'Saw' will continue for many, many, many chapters regardless of artistic merit, if there ever was any to begin with.

American shows last so long is because of syndication.

Strip/daily syndication

Off-network syndication can take several forms. The most common form is known as strip syndication or daily syndication, when episodes of a television series are shown daily five times a week. Typically, this means that enough episodes must exist to allow for continual strip syndication to take place over the course of several months, without episodes being shown again. If a small number of episodes exist, the entire run of the series can be shown in a matter of weeks. As explained by David Crane (creator and executive producer of Friends), "A show will go in syndication for sure when it has reached its 5th year or 100th episode. If a Network Show only runs for 2 years or so there is usually no demand for syndication." However, there are exceptions, such as the option is the 65-episode block (common in Children's programming), which allows for a 13-week cycle of daily showings, so there will only be four repeats in a year.
In some cases, more than one episode is shown daily. Half-hour sitcoms are sometimes syndicated in groups of two or four episodes, taking up one or two hours of broadcast time.

Sad, but true.