I have noticed that there is a lot of confusion surrounding USB and its formats and what performance you should expect from your cables and the ports they plug into.
Rather than pages of text with the occasional diagram I have found this Video which clarifies the current situation and also includes information of what to expect next in this field
Along this line, I've come across folks that don't catch onto the speed of file transfer is the 'cause and effect' of the computer having to first read the data source, store in temporary memory then write to the destination, takes time. The amount of that data versus the amount of free space such as a Temp folder has an effect. Also of note is the destination folders may have a different date of creation than the source [the files in them don't change].
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