High-lift mower blades are better at circulating and expelling clippings out from the deck of the lawn mower.
They’re great for scattering clippings across the lawn or keeping the underside of the deck free from buildups of clippings.
You can tell if your mower blade is high-lift by checking the ends of the blades. High-lift blades will have one edge bent at an upwards angle to create that suction needed to take the clippings and throw them out of the deck.