What does "not recommended for purchase" mean?

[jasonblewis]

Hi, many of the devices listed have "Not Recommended for purchase" on the page about the device. for example https://pvvx.github.io/BTH01/

it would be great if you could elaborate on why they are not recommended (as I have some I bought before I found this page)

but also if you could put Recommended on ones that are recommended, and why they are recommended.

thanks for the great project!