A rigger returned this gear to its owner with the reserve flaps closed in the wrong order. Closing the flaps in the wrong order can prevent the reserve parachute from deploying during both high- and low-speed malfunctions. The rig owner didn’t notice the mistake, but fortunately a fellow jumper performing a preflight gear check did.
Your reserve parachute is your last chance to land safely in case of a main-parachute malfunction, so it makes sense to learn the order in which your rig’s reserve flaps should close. Even riggers can make mistakes, so check the manufacturer’s instructions for your specific system to ensure it is configured correctly.