Yes. time can be wasted but its relative to energy & productivity.
Time being wasted means that you invested your time in immediate pleasures rather than greater, long term benefits. Think about it.
Always be aware of your return on investment and focus on future benefits. The knowledge you gain today will help you to be more valuable in the future. No matter what your passion in life is or what type of person you hope to be in the future, you should work towards that goal.
It's so easy for us to be lazy, to procrastinate, to indulge in immediate happiness. Yet it's so hard to work like a dog everyday, to get things done early and on schedule, and to work for the future.
The objective is to find a balance in between these two that allows you to be responsible and focus on fulfilling your goals, but not be miserable in doing so. Life should be happy and your hard work along the journey towards success should include more than a sprinkling of joyful times.