MadDog215 :
Some games I really want to play are on console platform only. All I see in PC are common genres with no innovation. There is no Destiny, GTA 5, Infamous Series, Metal Gear Solid series etc. Considering PC is the best experience ( meeting recommended system requirements). Why PC is not the main platform for almost games?
There are a couple of reasons. Several of which have already been mentioned in this thread.
The largest reason perhaps is that PC gamer expectations have become increasingly more demanding while developing AAA titles for the PC has become increasingly more difficult. Developing a game for a console is comparatively easy and streamlined. There's one (or two) target hardware platforms that are virtually guaranteed to stay static for the next 5 years at least. There's no need to fiddle around with scalability for different levels of visual fidelity, add support for different vendor components, or cede to the never ending list of PC gamer demands. Console gamers are simply easier to make happy and cost significantly less to do so, so many studios focus on consoles first and leave the PC as an afterthought.
With the above in mind, publishing companies prioritize production on the amount of expected revenue that the project is expected to bring in, and the risk involved with producing that product. It may be that working on a new product for a console makes more sense financially than porting an existing product to the PC if that port isn't expected to perform particularly well. An incredibly weak porting job may result in brand damage (Dark Souls, Resident Evil 4, GTA IV), as would a half-assed job across the board which take months to fix (Battlefield 4). In many cases, creating one or two quality products makes more sense strategically than reaching as many markets as possible (Nintendo approach).
Introducing a new product and introducing existing products to new markets are quite risky, the former more so than the latter. Brand new IP is often unsuccessful, which is why publishers looking to reduce risk often fallback on creating new iterations of established IP even if a winning formula is sacrificed to appeal to broader markets (such as the recent mockery that was made of Thief). New IP is often more successful on consoles than it is on PC, and many action/shooter games have made their debuts on those platforms first where reviewers and critics are more lenient. Some have gone on to become critical successes on the PC, but many have not. The reverse is often not true.
Piracy is also a huge issue. Many will prattle on about "marketing opportunities" and "failure of support" but at the end of the day piracy is significantly lower on consoles than it is on PC and to ROI chasing investors that's all that they care about. Investors do not care about whom enjoys the product, whom "would have paid for it had it included X, Y, and Z", or whom "just can't afford it right now but can't wait that long to play it".