I have a kitty litter bucket of spools of thread that my SIL got for $5 at a yard sale over a year ago. I couldn't begin to tell you how old that stuff is but it works just fine. Most are fairly neutral colors that I can use with anything and do with no issues. I've had a couple of spools with excessive breakage and out they go but otherwise I don't think I have to buy thread for 10 years!