Why do we perform Dissolution rest for 6 units (Tablets)?

[Ranjan.verma]

Why do we perform Dissolution test for 6 units (Tablets) only ?

Please anyone Sir,
Thanks & Regards.
Ranjan Kumar

[Awad (Dr. Ahmed Mohamed Awad)]

As per pharmacopoeias

https://apps.who.int/phint/en/p/docf/