This Counter32 counts the number of times an openSession() request failed specifically because the SSH client could not open a channel within an otherwise-established SSH session. Admins use this to spot a specific class of SSH-layer failure that occurs after successful authentication but before the actual application channel is usable, often pointing to server-side channel limits or configuration. For example, a server enforcing a low maximum-channels-per-session limit that's already been reached by other connections would cause this counter to increment on subsequent attempts.