cheerson CX-20 ENGINE TROUBLE

[Brown Rotors]

Hey guys I'm new on here and I am having some trouble. I am new to multirotors or RC at all. I bought a syma x 5c a few months ago. I just got a cheerson cx-20. After navigating the really poor instructions to get everything set up, I am having trouble with one of the motors not powering on with the rest. It will power up after you throttle up a little bit, but not when the other 3 motors come on. So my question is 2 fold is this a problem should I be worried? And why is it delayed in the start up?
Any help appreciated and again I have little knowledge about quads, so please keep it simple thanks.

 

[SleepyC]

You may have to calibrate the ESC's to the radio. With the props off, turn on the radio, put the throttle to the top position.
Plug in the helicopter. if it makes a different beep than normal, quickly pull the throttle back down. It should make another set of beeps. You are done. props back on and try to go fly.