As audience, our true purpose of watching a movie is to get entertained but on the other side, more than offering entertainment it is about making money on the entertaining product. The era of considering cinema as an art has been superseded by considering it as a moneymaking stream.
Given that, different formulae are being worked out for scoring success and here is a common observation. Many experts feel comedy is the only safe bet. For any movie, if it is in humorous tone only it is working for the audience and at the box office.
There are also few who like to watch serious movies but only if it is coming up with out of the box stories like Kshanam, Drusyam. The rest of the movies need entertainment or else they are dumped. Of course, there are also cases like Bichchagadu which are once in a blue moon incidents.