what does this mean?

Not really, the Best Before dates are printed for the approximate shelf life of that product. Also, in most of the Countries this is Mandatory to print. This actually means that the product is good and will not spoil within that Best Before period & for some items u can claim refund when the product gets spoilt within that period or may take legal action. Considering the Food items & medicine this should be taken care very carefully. Eg: Do not try with medicines after the Expiry Date, but can try some biscuits or cookies after the expiry date, if u want to.