"Qualifying stays" refers to overnight stays at a hotel or accommodation that meet the requirements set by a specific program or offer to earn certain benefits or rewards. Full definition
I kept members to 3s, I'm sure they were qualified, a few way over qualified, but I never had to go there to qualify them staying at 3 partners. (biggerpockets.com)
Additionally, members can choose to earn miles instead of points for qualifying stays. (wisebread.com)
Benefits of the new tier include earning 100 % extra bonus points on qualifying stays, or upgrading a friend or family to Platinum. (frequentbusinesstraveler.com)