In actual fact prisoners spend much more time interacting with other prisoners than they do with the prison guards. The “pecking order” then is more to do with the ranking the prisoners give each other than anything imposed by the guards. So then the older armed robbers, career criminals, are more “senior” than young dealers. It doesn’t take long before your young criminal forgets who is in charge. A guard might say “do this” and “do that” but in his every day life if an older lag invites a youngster into his cell for something against the rules then who do you think the young criminal will obey?