some do revert or turn wild No mater how much you handle them
but We have 50 some birds, 2 tame Tiels, 2 tame Quakers, 2 take Quakers as long as they're not near a cage, and a tame lovebird , all but one of my lovebirds are handle able w/out getting the snot bit out of you though they just don't like being handled. but will tolerate it.
none of the budgies are tame, had 2 tame ones for a minute - One is Muttley who I finished hand feeding once he was put with the rest of the budgies he was done with me, The other is Lance got him from a bird fair and he was tame, stepped up, Got put with the rest now we can't even hold him with out getting bit
the 4 baby tiels would rather just climb all over the cage and check everything out but they do want to be up in our faces and know what we're doing at all times They just don't want to be touched - and I hand fed them LOL the other tiels well they just want to watch and whistle at you they don't want to be touched what so ever and if you do hold one be prepared to leave bloody