People are idiots - My conclusion from the Inverted Spire
On the final phase of the strike in the beta, people just keep dying. The mechanics are easy enough to understand, but some still die for the stupidest of reasons.
1) Some guy didn't notice the several meter high Vex lord standing RIGHT NEXT TO HIM, and proceeded to get stomped into oblivion.
2) More often than I care to count, people die from the ground pound on the second phase of the fight. I can understand the first time it happens, but there are players who die every single time it happens. Do they not get that the floor is literally lava when he does that?
3) Instead of getting rez of someone who he's right next to (was behind cover too), the last guy standing chose to run around the platform in a circle while getting shot to pieces.
4) Got stuck between a warp gate and the floor when trying to drive a pike through it, got out of the pike, and fell to his death.
...that last one was me.