Hah, that's an interesting find alright; few power supplies have native 12+4 pin ATX 12VHPWR connectors; early adopters of the GeForce RTX 4090 graphics card will require an adapter cable to convert the 8-pin PCIe power connectors into a single 12VHPWR connector. 

Some premium overclocked RTX 4090 cards, such as the ZOTAC RTX 4090 AMP Extreme, including adapters that convert up to four 8-pin PCIe to a 12VHPWR, allowing the card to deliver up to 600 W of power. According to the ZOTAC AMP Extreme product page, you can read this:

4x 8-pin-to-12VHPWR cable (Limited service life with up to 30 connect / disconnects)

Perhaps this is a limitation set by NVIDIA for the maximum number of connection cycles the adapter can handle before compromising its safety as that connector is rather thin in plastic. The adapter in the image bears an NVIDIA logo, indicating that it is supplied directly by NVIDIA to AIC partners for custom-designed cards (and not counting on them to develop their own adapters). The 12VHPWR connector appears small, but it is capable of delivering 600 W continuously and 200% excursions, totaling 1200 W.

ZOTAC Mentions that ATX 12VHPWR Adapter can Connect-Disconnect 30x only