Here is a quick tip for y'all.
Whenever you roast a piece of beef, pork, chicken or basically any piece of meat that you will slice in order to serve it always remember to let that piece of meat rest for about half the cooking time BEFORE you slice it.
Why? Because while the meat rests after cooking, the juices redistribute through the meat.
For example, if you cook a piece of meat medium rare and slice it right away after cooking it will not look medium rare.
For the average home cook some of the more common items cooked at home is roast chicken or roast beef. If you give that beef or chicken about 15 minutes to rest you should be fine