how does poles and zeroes affect the step response of an transfer function?

Question

I have this close loop transfer function:

It overshoots, but why? The poles are placed such that that the damping = 1, so why the overshoot?

Answer 1

The zero in the transfer function has an anticipatory effect that you can easily see as an overshoot.

However, since the zero is in the left half of the s-plane, you can consider the pole-zero cancellation as a suitable technique to get rid of that zero.