"8 parachutes = one tangled mess"
They're not all out at once.
Big parachutes, like the main chutes of the Orion capsule, sometimes need some assistance to be pulled out to a correct inflation distance from the payload they're trying to soft land. So, smaller chutes are used. This particular process used by Orion achieves the following:
1) Stabilizing the capsule in the correct orientation for main parachute deployment (with the drogues opening in a few steps to avoid a hard shock on the capsule)
2) Small chutes help pull out the main ones
3) Finally the main chutes deploy in a few steps to, again, avoid a hard shock.