Apparently this poor fellow didn't know it's not enough to just look both ways before crossing the street.
All cyclist should know this by now, but don't try to rider in front of a car that is going at a decent rate of speed. You don't know how quickly they will get to you, and you could potentially get across the street slower than you initially anticipated.
This cyclist looked both ways and started to cross 'safely'. Unfortunately he did not judge the speed of big rig correctly (I will refuse from saying that the cyclist didn't see the big rig, that's pretty much impossible!).
Just use this as a reminder to look both ways intently, and never risk trying to get across quicker when you aren't certain it will be safe.