The concept of "hot" and "cold" slots refers to machines that seem to pay out frequently or not at all
https://blogfreely.net/connetbqxo/what-makes-an-addicting-slot-video-game-insights-from-professionals
The proposal of "hot" and "bloodless" slots refers to machines that seem to pay out in most cases or not at all, despite the fact those developments are in a roundabout way random.