There are so many variables that your questions don't cover.
How old are you? Your ability to learn the rules and the math/physics changes over the years. Your ability to train your muscles and hand/eye coordination changes over the years.
What are you flying? Staying with the same airplane and learning its quirks goes faster than flying in a fleet or changing from one type to another.
How is your emotional life? If you just got married, divorced, new job, lost job, new baby, friend or family member ill or died, new home, etc., learning can take longer.
Discouragement is part of the pattern. You start out uneasy and discover you can actually fly. You get excited and start to learn some of the hard parts, like landings and take offs that don't scare you -- usually. Then you solo and realize you are a responsible, trustworthy pilot -- maybe. Flying by yourself and learning the fine points of turns and stalls can make you almost giddy with accomplishment or despair when you just don't quite make it perfectly. Then comes the cross-country dual and cross-country solo, which is what this flying is really all about. Then comes the hardest part of training--honing all your skills to PTS standards. You become a harsh critic and missing your altitude or heading by a small amount on any maneuver undermines your dearly-won self-confidence. Finally, you make it and you know it is a major accomplishment.
You will plateau at each of these steps. You will get discouraged. Only you can tell whether you will persist until past the roadblocks.
Since I cannot answer the question about averages, let me add my experience. The day I passed my Private Pilot checkride, I also logged my 300th hour of flight time. However, there were many hours where I was so discouraged that I didn't even log my training flights. I averaged around 3 hours a week for 2 years. I had 13 instructors. Some quit to go to other jobs, some I fired, at least one gave up on me, some were at a chain school, some were at a small FBO school, some were independent. Some were great teachers, some were terrible. I flew three kinds of aircraft, a C-152, a Piper PA-28, and a C-172. Eventually, I found an instructor who meshed with my learning style and together we made it. There is no way you can coerce me into counting up the thousands of dollars it cost. It doesn't matter. I won the prize.