Handicap Frustrations

I had been keeping my scores and handicap using Swing by Swing but finally joined a club and entered all my round history. Found a HUGE difference between my USGA handicap (21) and Swing by Swing (15). My scores range from mid 80s to mid 90s.

But I found the error was mine!! I play from the senior tees but had not indicated that on SbyS! Once I adjusted that, the two handicaps came into sync fairly close!

But I use to think I was a okay golfer and now I know the sad truth . . . I suck!

I had the same issue when I switched from letting Golfshot dictate my handicap and switched to an official one My USGA one ended up jumping up about 4 strokes.