Funny isn't it - we're exposed to so much great music these days (thanks GT!) we can't help but want to play better across more styles with often very little time on our hands (sic) to achieve our desires. Frustrating isn't it? Moreso, we may equate regular long practice sessions with solid development - one hour plus a day is hard won (if at all) amongst regular work and family matters. And if an hour is not available many opt to wait until it is, sadly missing out on guitar time for days (or weeks) on end.
One way of tackling this is via several short sittings each day. Coincidentally, this 'little and often' approach ties in with our attention span - intense concentration tends to work best in quarter hour bouts. So be it a technique exercise, a rock solo segment or a chordal jazz arrangement, several fifteen minute segments a day is as beneficial as a one hour session broken into fifteen minute breaks. Indeed, spreading out your sessions during the day may heighten your playing enthusiasm!
So don't wait til that magical day arrives when you can spend an hour or more playing. Take action now and grab that fifteen minutes with gusto!