Repressing your natural urges is pretty bad for your mental and loveual stability.
In other words, procrastination is healthy for both the mind and soul 
In other ways it is bad.
Eyesight, which is already terrible.
Your sanity, you can become addicted. You'd probably want to get home just to fap.
Your mind, it goes dirty.
Your criminal record, depending on your country and age.
And various other things.
