When should meat be seasoned?
I heard that salting meat prior to cooking draws out the moisture but I have noticed that a number of chefs season their meat prior to cooking.
There are different 'camps' when it comes to seasoning but essentially If you season meat too early before cooking, the salt will draw out the moisture, meaning a less juicy piece of meat, however if you season just before cooking the seasoning will help to impart flavour into the meat. If you seal the meat and then season it, the sealed meat will not release any juice. Hence the two theories.
Salt is a very unique "spice" (technically it's a rock). You could literally spend an hour just learning the various ways it affects foods.
A general rule of thumb is that the longer the meat is exposed to the spice, the more it will pick up the flavor, but there are many variables in how fast this happens, how deep the flavor penetrates, etc.
For example, in brining (soaking the meat in a salty liquid), first the lower salt juice is drawn out of the meat, then the saltier water is drawn in along with the other spices in the brine mixture. The salt actually helps the meat retain the moisture better during cooking.
Covering a raw steak with salt for a while before grilling will draw out the moisture and change how the steak is seared.