Every video I see or recipe I read directs me to, "Be sure to get a coating of rub on all of the sides, too."

Why?

When a cut of meat is carved to be served, those people who get a piece that contains the sides get a serving that has seasoning on the top and bottom, like everyone else, but they also get seasoning on a third portion, the side that was seasoned.  That's 50% more seasoning.

Or, consider a tubular cut of meat like a loin or tenderloin.  When it's carved and served the seasoning is typically on the served pieces' perimeters.  But those people who are served an end piece also receive seasoning on one of their piece's faces.  That's many times more seasoning.

Am I not thinking straight?   Or are these people who tell us to season all surfaces not thinking straight?

What do you think?

I season every piece of the external part of the meat.  I also trim most of the fat off of the meat before applying the rub.

I used to shake my head when my brother would apply rub on the fat cap of a brisket for his business and then cut it all off before slicing and serving.  Why waste the money to apply the rub on the fat if you going to cut it off after cooking?  It's not going to penetrate through the fat.

I season every piece of the external part of the meat. 

So, say on a trip-tip or brisket, you season the edges?  When you slice it to serve it, the people who get the end pieces get more seasoning than the others.  It must be noticeable.  Has anyone ever commented?

I also trim most of the fat off of the meat before applying the rub.

Me, too.

No one has ever had a negative comment about too much seasoning on anything that I have made to my knowledge.

 I am with Lew on this one.

 I season all over & every nook & cranny after trimming the undesirables.

I'm with Paul.  I seldom season the sides.  It seems like a waste of rub since the top and bottom are seasoned.  And if it is a thinner cut I just season one side because I tend to over do it at times.

I rub the sides just because it seems like the thing to do since you are already putting it on top and bottom.
But, I agree, probably not necessary.

Depends on what cut it is and how I am cooing it. For large cuts like butts or roast of some sort I try to do all sides, for chops and steaks usually only top and bottom even if they are thick cut.  A lot of the time anymore I only salt steak or chops if I am doing on the grill, griddle or pan frying.

I guess I am having a hard time visualizing the cut and the issue.

Good question. I have always cover it all when it is a thicker cut: butt or brisket, meat loaf etc. and just the top and bottom of thinner cuts, steaks, chops etc. No problems with lack of seasoning on the thinner cuts. However, I don't care how others do it either as long as their offering tastes good to me. So I would label this good question as a non-problem.

I guess I am having a hard time visualizing the cut and the issue.

Think of a bread loaf.  The bread crust is comparable to the seasoning on a roast like a rib roast or loin.  The end slices of the bread loaf have much more crust than the interior slices.  Just as the end slices of a roast have much more seasoning.  I Quit quit seasoning meat edges and ends so that the seasoning is more even.

It's never been an issue for me.  But it annoys me when "experts" preach things that are obviously incorrect if one takes the time to think them through.

EDIT:  Added a skipped word.  Necessary changes in blue.

You know that why I like it here. You folks are like me on some things. We just look at something an way over think it or something like that. People tell us something and we think about it and wonder how that makes sense, even on the dumbest of things. At times I think I should find a hobby. The GF asks me same thing, where do you come up with some of the things you do.

I get it, and understand now.  For me, my brother always like an outer piece with lots of seasoning, so always a built in solution!

I think your reasoning is absolutely right Paul. But I am one of those folks who love the end piece because of the extra seasoning, so maybe done for folks like me!!!

Kinda like "how do you like your eggs?"  No two answers exactly alike.
A new thought came to mind.  When you don't season the sides of a steak or even a roast;--As the meat is cooked the juices from the top side drip down the sides of the meat and supply the naked sides with lots of seasoning anyhow. Perhaps not as much but probably plenty by the time you turn it over once or twice.  And if being braised, likewise. ??