Some imitation small capacity memory cards claim to be sold as large capacity cards.
2. After some devices have been tested, MicroSD cards may be maliciously partitioned and devices can only read the partition partially.
3. Because the manufacturer's capacity formula is different (the actual measurement unit of normal capacity is 1024KB=1MB and the manufacturer's measurement unit is 1000KB=1MB), the actual capacity will be slightly lower than indicated on the card label.