Standard PC/Mac/Linux executable, for a number of reasons:
- Raw performance: PC games are the fastest possible platform, meaning you can make the most of the graphics rendering pipeline and really squeeze out every ounce of performance (as in many cases, higher performance can lead to a smoother/better experience if your game is sufficiently complex).
- Stability and consistency: A normal PC platform is very consistent in that the environment wont really change whilst the user is playing a game, nor is the running of the game directly dictated by anything else (ignoring intrusive programs like anti-virus software), meaning no interruptions, options for full immersion and consistent expectations of external hardware such as a mouse and keyboard, so that you can design your interfaces and interactions to be as clean and easy as possible whilst also supporting a good range of input.
- Scale: If you want to make a game which has a large number of high-quality assets, or generates larger save files, the size of file that is acceptable for web-based distribution is far far far smaller than what is acceptable on a desktop. Similarly, loading for even moderate sized games can take longer and is entirely dependent on the users internet speed. People's access to your game also relies on access to internet and that your server can handle the volume of players you may be dealing with.
-- Same holds true for console platforms (PS3/4, XBOX), though for slightly different reasons and those platforms do also do a better job of being more optimal in cases, and also disconnecting you even more from external distractions.
I personally don't like HTML5/Mobile platforms, though that is more to do with the style of game I prefer to develop. I dislike those other platforms, mostly based on their "loose" feel. For example, phone's and web browsers are very interrupt-able platforms. Catered well to short-playtime games that you can play in bursts, but I don't really like the casual gaming style for my main gaming. Sure, I play mobile games whilst waiting for the bus or sitting in a waiting room, but when i'm at home, I much prefer an experience that is a little more immersive and disconnected, regardless of what the game is.
My biggest pet hate with HTML5/flash games is how easy it is to accidentally close a game. It sounds like that's more my problem than a problem with the platform, but there will be times i'm playing a web-based game (turn based chess for example) and i'll click onto my other monitor, briefly forget about the chess tab and mass-close a chrome window.
Note that I don't think the platforms are bad as such, I think the platforms do a great job for what they are, however it's more that for me, the use-case doesn't line up with what I want to create