Beef tastes much better when it is aged. It has better flavor and is more tender and juicy. So what is the optimal age for beef before consumption? Simple answer is 14 to 21 days. I prefer 21 to 28 days on my steaks and roasts. But it depends on the cooler holding temperature. Research shows that meat ages best from 0 degrees to 4 degrees C. Colder than that, and the beef won't age much and warmer than 4 degrees C and the beef will age too fast. In general, studies show, no real advantage to aging over 14 to 21 days. Now, keep in mind that Tenderloins don't need much aging; they are already tender! But they do taste better with 14 days of age. Tenders cannot be aged as long as say, Ribeyes or Striploins. They will taste "livery" if aged past 30 days in a warmer cooler.
Burgers do not need to be aged at all, in fact, the fresher the better. I have completed hundreds of blind taste tests with panels and the freshest ground burger almost always wins the cutting/tasting.
Watch the pack dates on your beef primals and if you throw out the box, make sure you write the pack date on the primals with a marker and label. In a warm cooler or kitchen you can ruin a great piece of meat by over aging. Check the dates on all your food deliveries and make sure you are using the oldest meat first. Freeze anything that is over 30 to 40 days of age. Watch for signs of bacteria growth in the bags like air pockets or blown bags. These are signs of too much age or heat abuse.