If it ain’t broke, don’t fix it. You mean like our 31-year-old furnace that works but is guaranteed to give up the ghost any time now? Or the back deck that’s propped up in one corner because it was falling off the house?
I think you could definitely say this about software because almost all their “upgrades” which supposedly fixes inevitably make the simple stuff more complicated and the complicated bits unusable.
On the other hand, when it comes to the things in your household? Replacement or repair before it blows up, burns down, or collapses leaving holes in ceilings and potentially causing life-threatening injuries to persons or pets? Maybe you really need to fix whatever it is sooner rather than later.
Fixing that broken toilet for $900 was a lot cheaper than replacing the floor, ceiling, and burying whoever was sitting on it when the floor caved it!
So maybe this needs a minor wording change:
IF IT IS WORKING PROPERLY AND EVERYONE USES IT, LEAVE IT ALONE. IF IT’S HARDWARE AND IT IS ANCIENT, CREAKING, AND WILL FAIL LEAVING A TRAIL OF DISASTERS IN ITS WAKE? CALL A PROFESSIONAL AND CHECK HIS OR HER REFERENCES BEFORE YOU LAYOUT ANY MONEY!