March 1, 2018, 1:34 a.m. -  fartymarty

I have had a little think about this... As humans we like to get better at stuff and see progression.  There maybe difficulties but you overcome them and progress.  As a result you get a sense of enjoyment or fun.   I guess you could call this learning - whether it be physical or mental learning.  When you stop "learning" either by not overcoming the difficulty or are not challenged then you stop "learning" and it is not enjoyable or fun.   Maybe stagnation v progression is a way to describe it. This can relate to many things from your job to mountain biking.   The advantage I see with mountain biking is there are many aspects to it - fitness, strength, skill (on the bike and in the workshop).  As such you can trade one off for another and still have fun.  Also something as simple as changing bikes (back to a HT or rigid or to something easier like a FS bike) or changing seasons can make things easier or harder and allow you to progress.   As a beginner you are learning a lot quickly.  As such probably get the most enjoyment.  As you get better the percentage increases are smaller and you have to work harder for them.