He did it because he enjoys notoriety. Those things hold value for him. Which it did give him notoriety. Unfortunately too much. Just because you don't value internet cred, doesn't mean he doesn't. I think the difference of why you think he is dumb is because you think it's stupid to value internet cred. Which is subjective, but irregardless, there is a low chance of him being able to achieve the success he acquired by not being reasonably smart.
Exactly what clinical trials did he sponsor (answer-none)? He's done absolutely nothing to make the world a better place, and lots to make it worse. It says a lot if you think anything positive about this asshole, he's really done nothing worthwhile in his life.
Convicted swindler Martin Shkreli was decreed a “danger to society” Wednesday and jailed by a federal judge following Facebook posts in which the loudmouth former drug company exec put a bounty out on Hillary Clinton’s hair. That's what he was jailed for - you might want to read the original link
Prolly when this guy was a child he was allowed to roam freely with no discipline from his parents. The sort of kid you will meet in a posh restaurant who is playing up causing a commotion while parents thinks its ok or amusing. Also the sort of kid who is sitting behind you in an aeroplane kicking the back of your seat, again with parents doing FA about it. So he grows up thinking he can do as he pleases. People are largely a product of their upbringing. Parents have a responsibility with children to give strict but loving guidance, because one day the chickens come home to roost.
https://www.quora.com/What-are-the-good-and-bad-things-Martin-Shkreli-has-done I also read about that account in an article a while ago, but can't find the original article and don't recall where I read it. Like others here have said, he's obviously made some mistakes. The security fraud was obviously wrong, but hopefully his sentencing will heavily consider that no one lost money and some made huge returns. So yeah, he's made some bad decisions and seems to crave attention, but he's also done some good. Watch his Youtube presentation made at Harvard. I think you'll see that's he's not as bad as Buzzfeed and MSNBC claim that he is.