(assuming that certain devs hated it and thus reason why it was delayed.)
Armor Packs and Lvl 3 turrets removed
Molten core moved to replace it as an ability, Likely 30 sec cold down. (likely removed connection to turrets.)
Head box reduced.
Reload Time Reduced.
New ult, (Taken info from the Art of Overwatch): early ability Concepts - One of Torbjörn’s early Abilities was a Trap, (shows pics a chain ball opposite page) that could fire a chain that hooked onto enemy players and kept them within a certain radius of the device. Using it was the type of skill that people(edit: Devs) either loved or hated. In the end, the team scrapping the ability and replaced it with Armor Packs.
(Then the above into an ULT.)
Plus the Turret changes, where Turrets were throw-able and upgraded on their own. (Likely could still upgrade them with the hammer if your wanted.)
Also Two turrets.
Other changes for Balence reasons but this is likely what half of the Devs wanted.
Before this was scrapped by a disagreement with the other half.
also just adding this