Although this could save time, it actually isn't beneficial to your cooking or health. Some spices could have been saved in their glasses for a long time now and of course you can image that they are not extremely high quality spices either.
Spices are best if kept in dark containers in a cool and dry location. Some spice racks have spice jars that are made from clear glass. Of course this looks appealing and you can see how much is left in your spice jar, however preferably it's not the very best container for your spices. If you utilize your spices frequently, then a small container made from glass is fine given that you will certainly have to renew it more often and the chances of getting stale will not occur.
If you do have a spice rack with clear glass then you might want to go through it and exchange all your spices for fresh, natural and more great smelling spices. Buying natural spices in bulk will certainly save you money. Just make sure you only refill your glass spice with a smaller amount and afterwards keep the bulk of the spice in a dark container, glass or re-sealable plastic foil bag.
One spice to exchange would be the shop purchased "cassia" cinnamon. Try the aromatic citrusy taste of Ceylon cinnamon powder. It is healthier and more great smelling not to mention more secure also. Try sprinkling a bit on your morning coffee or mix in your pancakes. Such a dream!
Cooking will certainly be much more fun, given that it will certainly taste much better and it will certainly be healthier for you too. So get going and throw away your stale spices today.