As an instructor the spread for all my students was 4.6 hrs to 24 hrs
The 4.6 hrs was a 17 yr old who had about 600 unofficial hours on his fathers
Supercub, Cessna 185, and DH Beaver (all on wheel, skis, and floats).
The 24 hrs was a middle aged housewife. She was ready to go earlier but just did not have the personal confidence. One day after a good flight she turned to me and said " I'm ready " so I got out of the airplane and sent her on her way.