This is your life. This is real. This is not a dress rehearsal. Your time on this earth is finite. You'd better make it count. If you're just trying to survive, I feel you. But if you're past the struggle for survival and don't have to worry about basic necessities, then you have no excuses. At 25, you'd better have a sense of direction. At 30, you'd better be in the mix and working on accomplishing something significant. Don't get shook and cry about how I'm such an asshole. This is all true. Whether your big life goals are education, fitness, family, art, business, faith, or some combination thereof--by 30, you'd better be getting it in on one or more fronts.
Most people spend their entire lives obsessed with the past and dreaming about the future. They are never fully alive and present right now. Most people put off accomplishing their dreams and goals until next month or next year. They imagine a future in which they've figured everything out, gotten everything just so, and can finally focus on achieving X. That future never comes. Years go buy. The 25 years olds who bullshit about their plans to do something great quickly - in the vast scheme of things - become 45 year olds who have done nothing.
Mortality is a powerful motivator. You only get one. Make it count.