It's not an exhaustive list of things people are bound to experience in their life, just examples of how the phenomenon can manifest. Also, don't take 'self-destructive' as some kind of criticism, or some shameful, dirty little secret that people harbour. It manifests itself all the time, in little things you do or think that prove or could prove detrimental to your life. That, or you've led an incredibly dull, puritanical life.
Again, I'm not trying to say that people are inherently prone to self-harm, or self-loathing to the point that they're one sneer away from throwing themselves off a window ledge, but can you honestly say you've never entertained musings of an action or deed that could only lead to a negative impact on your life? Or is thinking of jumping off a really high place a bold move to better your lot?
It's not really that at all.
I get a buzz out of an adrenaline rush, I love speed and to take a chance and give something a go, if someone came up to me in 1 hour and said they have a tight rope walking opportunity off the waterside tower blocks I'd be game for it, that doesn't mean I'm going to go out and self harm myself any other time, that's just silly

- I love the feeling of control. a control freak if you will, and knowing that I am safe yet can enjoy the adrenaline because I'm in control is what satisfies me. It is a hunger, a positive one at that.
It's the reason I've started Urbexing (that and for the photography's sake) and also will shortly start rock climbing.
The buzz and the excitement is something unmatched by any psychological definition and not everything like this can be put onto a simple paragraph to explain it away like you've attempted by saying it could lead to something negative in life but most certainly in my case it's the direct opposite.
For many people a risk every now and then provides ample satisfaction in their daily life but that doesn't mean their lives without said risk taking place is dull and meaningless, again in my case I have a perfectly healthy and meaningful life with friends and family who care and with a solid future in 2 career paths.
Like I said, not everything can be justified with psychology how you seem to think!
Too many people live their lives these days behind the wall of safety, safety this and safety that, they're not taking chances and not getting the buzz they need to get a feeling of what adrenaline is and I think this is why many people live a robotic life - get up, go to work, go home, sleep - the 5 day a week re-cycle.