weblogic, difference between Failed Reserve Request Count and Waiting For Connection Failure Total

weblogic, difference between Failed Reserve Request Count and Waiting For Connection Failure Total:

JDBCDataSourceRuntimeMBean.FailedReserveRequestCount
The cumulative, running count of requests for a connection from this data source that could not be fulfilled.

JDBCDataSourceRuntimeMBean.WaitingForConnectionFailureTotal
The cumulative, running count of requests for a connection from this data source that had to wait before getting a connection and eventually failed to get a connection.

I think the second is just a subset of the first (in fact in our server we have plenty of FailedReserveRequestCount, but no WaitingForConnectionFailureTotal). If a DB fails, surely you have the first error, never the second.