It is almost impossible to use what should be the natural juices from meats to make sauces etc. if the produce is purchased from a supermarket!
I have just drained nearly a whole cup of water from 4 pork medallions as they cooked.  This rubbish food may seem OK to the thousands of 'too busy' people who support the culture of convenience food but heaven help all of us who care what we eat if all the independant 'proper' butchers disappear!