Tim, you are so right!
I think the average person owns a machine for 10 years. That's what it said in a magazine with a section about looking for a sewing machine. I think it is really longer than that.
Elaine~ it all depends on how well you love your old machine.
My Mom has a Brother she bought new about 26 years ago. She recently got a new one. She wanted something with a few of the new functions. A few different stitches, an easier reverse, something a little lighter. It was the cheapest one, about $77. I'm sure she will have it forever. She still has her old one.
I did upgrade to a newer one. I wanted the embroidery function. ;) I still have my cheaper Brother. I'm keeping it, too.
You could get your old one cleaned/repaired and have the same as a brand new machine.