Is there oil left after you vape?

[Psychoholic]

Hello new here I bought a vaporizer with these glass bottles essentials vaaapp type and I was wondering if all the hash/concentrate burns all the way up or after its done vaping does it leave a brown/black oil left over or does that mean there is still some left and I just keep heating... sorry for the run on sentence but I medicated right now and its bed time...
also if the oil is just left over should i clean it out often?

Thanks for any and all info on this...

 

[CentiZen]

Depends on the purity of your product. The good stuff will just vape away totally with very little residue. That may or may not be the case depending on your producers quality