Used Tractor Values

then got replaced by an inefficient machine during industrial revolution and is now evovled into an efficient machine with little or no human interaction needed and later has the potential to not need any assistance from humans at all. Its for a paper im trying to find an example. i was thinking about doing on regualr agriculture like a simple scythe to a huge tractor and so on but i was hoping to get maybe a better example if anyone can help.