Think of spices like coffee: there are different grades of quality and freshly ground is always best. Good, young spices will be rich in essential oils but these precious aromas drift away with age, especially once ground.
Ideally, you should buy spices whole, in small quantities, and grind as needed. There is still a place for convenient pre-ground, but refresh often and be aware that their intensity may be dulled. (With ground cardamom, for instance, you will need twice as much as if you grind the seeds fresh, and the taste canโt compare.) Store in airtight containers away from heat and light. Finally, old spice must go! Smell: there should be an intense and appealing fragrance; there should never be a dusty disappointment.