Your not a dumba$$, not even close. At the worst, I'd simply say your naive, but thats not really fair either.
I can't say how much, or what kind of DD you conducted. I can only judge what my own naivety has done to me in the past.
Like I said before, thats no longer an issue, as I won't conduct any more DD than reading recent PR's to look for an explanation for a stocks recent decent, since we love gutter plays.
If there is a stock or company I somehow feel may be for real, then I'd flip it enough times to build up free shares.
But most times, like today, I won't stay in a stock if it starts going down. My usual pain threshold is about 15% to 20% and then I'll cut it loose, like I did today with VSPC.