what dose it mean if a paint has no shelf life

Think of "shelf life" like the expiration date on a carton of milk - essentially, it is the length of time an item remains useable or is in a condition to sell. 

If the paint has no shelf life issues, it should remain good as long as it remains sealed, without having to worry if it's gone bad sitting around waiting for someone to buy it.

As for how long the paint remains useable after you break the seal, your experience may vary. MMP is supposed to be good paint, but most every brand of paint tends to act a little funny after time if you're not careful with how you store it.

Hi;

    I think that in modeling that refers to the paint after you open it. Now if you don't use it out of the bottle, Then shelf life becomes the issue. Not using it straight means a lot. Thin it and you change the viscosity and gassing out time and quality. Thin it say 50% and you've got a whole new dog in the hunt.

    Unadulterated, from the bottle means the shelf life of what's left in the bottle is up to you. I am saying that if you don't clean the bottle rim and top you may not get a good re-seal. Paint not thinned, will last a long time. I've got a lot of Model Master metallics that are over ten years old.

    Those were Enamels ( Oil Based),Their new stuff ( Acrylics ) Doesn't seem to want to cover by brushing. It comes out uneven and blotchy. I have had two of the acrylic colors ( Red and Green ) skin up in the bottle. And I had done the cleaning I mentioned. So Who really knows. I have found too, if you buy extra bottles to put your mixes in, Buy Glass not Plastic.

        This I learned the hard way. Had some beautiful Kure Arsenal Japanese Imperial Navy Grey in ten bottles. When I went to use it it was rock solid in three of the bottles, and I used them New!      T.B.

KT and TB covered what shelf life means.

I'm curious, where did you hear Mission Models paints have no shelf life?

With Mission Models Paints, according to MMP “shelf life” is different because ( uppermost)

https://www.missionmodelsus.com/pages/tips-and-tricks-faq

I have “a-hemm” several of the colors as well as thinner, poly additiv. primer, etc... .

Unfortunately, I cant comment, from experience, regarding “ shelf life “.

I like the paint qualities, it IS different from Tamiya for sure. Mission Models Paints are their own ”system”, if you will.

In full disclosure...I am a complete re-noob.

Thanks for the link.

So in para two, MM says..... "This is an advantage to you. This means consistent blends and you will never get a bad bottle of paint and no shelf life."

I read that to mean we should expect very good shelf life. I don't think I have this backwards. I remember reading that page earlier this year before ordering some MM paints.

Like you, I haven't used them long enough to comment, but the few jars I did open and use probably early spring are certainly like-new.

“No shelf life” means the jars of paint don’t get invited to the mixer parties on the paint rack.

OK I’m getting my coat.