Everything's a Continuum

Lindsay is knitting a 2 x 2 rib scarf.  She's more than halfway done, and has passed the sweet spot between mastery of the learning curve and boredom.  That's the trouble with any knitting sufficiently challenging to keep our interest, isn't it?  I tried to explain it to her, but ended up drawing a picture (Surprising nobody.  Visual much?) instead.

What do you think, Gentle Readers;  Did I explain it right?  I think this concept is pretty much the whole reason why we knit.  It's all there: Start-it is, the learning curve, abject frustration, smug satisfaction, even project abandonment.  We're all just looking for that Sweet Spot.