MAC refuses to wake up

After closing the lid for my mac to sleep, my MacBook Pro refuses to light up even though the caps and numlock button lights up. The screen had no response but the sleep light was off. I was forced to restart the system by holding on the power button to reboot. It is not new and I have encountered this issue too frequently by now.

I was wondering why my intel mac doesn't wake up instantly when you open up the lid and hit on any key?