"That's very rarely the thought process in the real world when you're dealing with a production system though. Most developers who have the seniority and experience to make the call to upgrade something aren't just upgrading for the fun of it."

you and i's experience varies greatly, Ive worked at a number of firms that update things based solely on age(and boredom) and nothing else... thats what happens when non-tech people steer the ship. I also see this happening a lot to justify someone existence on payroll.