Makes sense Pete that Tessio's domain being adjacent to Barzini's was easier, convenient pickings than Clemenza's. Tessio was unlucky!

Tessio: [fish tank scene] with Vito gone, me and Pete will come under Barzini's thumb sooner or later Looks like Tessio chose sooner!

Patience is a virtue Then they could “all live happily for a hundred years”

If you could ask one question
Did Clemenza really pass the loyalty test? though or

Perhaps Clemenza was just lucky! by sitting tight and doing nothing because he was not losing his territories, got away with it?
ie: Clemenza's loyalty was not tested?