The real and solid explanation for more than 1 Couchbase environment misconfiguration

I’ve tried to google and search around forum for more convincing answers on this topic.
The below are what i’ve found:

  1. developer.couchbase…com/documentation/server/current/sdk/java/managing-connections.html#concept2677__concurrency
  2. More than 1 Couchbase Environments found
  3. Getting out of memory exception while creating multiple couchbase Environments

Yet, I still do not understand what are the actual “unpredictable behaviors” and “resources” the answers above referring to. Anyone can help to give a more detail explanation please?

Assume I’m using Java SDK with DefaultCouchbaseEnvironment builder, if I build two environments with different timeout/kvendpoints/other parameters, how would one affecting another? Is there any static shared module in the environment?