Electrical cord wrapped in a circle cause problems?

I'm way at the end of this, but I'll add one more true-story mystery to see who can solve it -

While In the AF at a high tech facility I once held a multi-wire cable in my hands not coiled - with each end laying on the floor - and there was a voltage we measured across a couple of pins of the connectors on each end. What caused this?

Hint: I had to destroy this expensive taxpayer provided cable to solve it.