Thalia's Lieutenant/Diregraf Colossus

Assuming these creatures are on the board alone:

Colossus Scenario

Play the card

Starts as a 2/2

Sees itself for its first ability as a zombie you control upon entering battlefield and gives itself +1/+1

Gives itself +2/+2 for the trigger of its second ability of a zombie coming into your control

Ends up being 5/5

Lieutenant Scenario

Play the card

Starts as 1/1

Sees itself for first ability and gives itself +2/+2

Gives itself +2/+2 for its second ability of a human coming onto the battlefield

Ends up being 5/5

When reinforcing these creatures, the Colossus gets all bonus effects upon entering battlefield but Lieutenant does not. So 2x Colossus yields a 10/10 creature (assuming no other zombies on board) and 2x Lieutenant yields 8/8 creature (assuming no other humans on board). One of the +2/+2 triggers isn't happening for Lieutenant.