can seeds become not useable?

I was wondering if seeds can get to where they cant be used. How can u tell if they cant be used?

if they get crack or crushed they couldnt be used

Seed becomenon usable when they no longer germinate. We have seen open seeds germinate as well as some with minor cracks. They are very tough! Seeds remain viable for up to four years stored in a cool dark place but the germination ratio drops after about 2 years. If they are kept in the refridgerator we have seen seeds remain viable for up to six years. Seeds should be dark, plump and when cracked open be white in the middle with good structure. Hope this helped! ;)
Check the picture. The small seed that is discoulored is not classified as healthy!

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if u piss on them and put it in a ziplock bag on the window sill so mold grows on them they're bad seeds..

The color is a good indication usually, if they are whitish instead of brown/black, they have not a good chance to germinate. Another trick is to push down on the seed with your thumb (not full force), if they break they are dead seed. The best way of course is to simply try to germinate them.

thanks guys u helped me out a lot