LG G5 and HTC 10 will not complaint with USB Type-C Spec: Back in November last year, the Google engineer Benson Leung explained that if a device or a charger uses the Qualcomm Quick Charge 2.0 or 3.0 technology then it is meant that it coexists with the USB Type-C specification. He said that the Qualcomm’s QC3.0 and QC2.0 uses the proprietary charging methods including the variable voltage method that will change the Vbus above the 5V, something like a USB Type-C specification forbids.
LG G5 and HTC 10 will not complaint with USB Type-C Spec : says Google Engineer
It means that any device which is using the Qualcomm QC will go against the USB Type-C spec and for those who are wondering how are the LG G5 and HTC 10 comes in the scene, this is because the flagship smartphones will support the Qualcomm QC technology that is clubbed with the USB Type-C. On the other hand, the Sony Xperia X series and Samsung Galaxy S7 also do not support the Quick Charge.
I personally do not recommend any Qualcomm QC 3.0 USB Type-C charger, because any of them claims to support the QC 3.0 in a Type-C port that violates the Type-C specification, stated by Leung as a reply on a Google+ post. The Type-C spec specifically forbids the proprietary charging methods that will try to change the Vbus beyond 5V.
However, the exact threat for using the Qualcomm QC along with USB Type-C is not yet clear. According to the Android police, the USB Type-C was tested with non-proprietary charging at 5V and was found almost safe to use. But increasing the volts may end up harming the device. One limitation of using the Quick Charge on USB Type-C is that the users will not be able to use the data connection at the same time.