Recovery account is a feature whereby if your account ever becomes compromised you can reestablish your ownership, change passwords, etc. with the help of your recovery partner.
Since many accounts were originally created by Steemit Inc., that is their default recovery account which is no longer trustworthy or responsive to needs of Hive users.
PeakD states in their post
The recovery account should be set to an user able to verify your account owner identity and cast the required operations to trigger the recovery process.
More tools to simplify this process will be available in the upcoming releases ;)
So in simple language, for now I’d simply set it to any other Hive user who you trust and know you could get in touch with in the event their help is needed. If they’re very tech savvy that’s a plus! Hopefully @peakd has tools up their sleeve that will enable average users to help each other efficiently should the need arise.