I think the key idea is that White needs to play only forcing moves, for example 1.Qh5 allows something like 1...Qd6 and you don't have anything, but with checks you can shimmy the Queen into the right positions, enabling the rook to join the battle. Also with the Queen on the e-file later, it prevents the Black Queen from coming to e1, and frees the rook to lift up the board.
I guess that its rated so low, because every patzer plays a check and then stumbles across the winning line after the not so hard to spot 2.Qxh6+ and 3.Qe6+
https://www.chess.com/puzzles/problem/2420172
Hi, I spent a good hour solving this puzzle, only to miss it. The problem with this one is that the correct move forces black to response in one way only, while any other response leads to checkmate in 10+ moves. That seems very hard to predict for me, much harder than the usual puzzle in 1600 - 1700 range.