Durability of the J4 Connector

Hi, After only 2-3 insertions / removals of wires into the J4 inputs, today the release tab on the + pin snapped:

After a brief inspection, the whole cover came off, the very small tabs under the metal clips had broken:

Any suggestions here? I am interested to understand what the designed lifetime for these connectors is - is this expected, or is this perhaps a Quality Control issue with components?