card performance

After tests on my samsung galaxy tablet with SD TAB4 bench, writing and reading speeds are less than the specifications given by Samsung. (40 mo A50 / s for reading and 10 to 20 for writing instead of 90 and 80 maximum specified by the manufacturer).
So I inquired with the support of Samsung "memory card" who asked me if my tablet looked UHS1 secure digital interface that allows the operation of UHS1 map mode. So I asked Samsung to support "tablet" by téléphone.Je could not have the information requested. He would call me.
I think my tablet interface is not compatible with the UHS1 map mode, which explains the slower speeds than the maximum speeds advertised by the manufacturer. The SD card is designed for HD camcorders or cameras that has this UHS1 interface and not for smartphones and tablets in my opinion.
In conclusion, it is useless to buy a super fast card if the material does not take into account!