I read once somewhere that one of the biggest challenges that Charles S. Roberts faced when he invented the commercial board wargame was explaining to players that they could move more than one piece on a turn. That they could, indeed, move every piece on a turn if they so chose. This idea is so central to the illusion of maneuver that powers the hex-and-counter idiom that we who speak its language sometimes fail to recognize how strange and extraordinary it really is.
This gaming table constructed in Mainz, Germany (1735) and displayed in the Cleveland Museum of Art combines chess and nine men's morris boards.
For thousands of years, mankind has played games, and in the vast majority of those games, one does not get to move all of their pieces on a turn. Chess, draughts, go, Nine Men's Morris: in all these games, the players alternate moving a single piece. Let's call this prevailing form a unitary model; next to it, the idea of moving everything was absolutely alien.
To a degree, it still is. I had a friend who was interested in wargaming, and I started him off with a fairly simple hex-and-counter game. Every turn, he would nudge one counter, and I'd have to remind him that he could move as many as he liked, in which case he'd move two more. I'll say this, it made for quicker turns.
I'll admit that that might be an outlier, however. Other newbies grasp the concept readily: yes, I can move all of my pieces, great. Where they run into trouble is figuring out where each piece should be moved. I think the problem stems from the idea, so central to games that follow a unitary model, of a good or clever move, of one piece, moved decisively and just-so, leaving your opponent no choice but to stare at it, gob-smacked by its brilliance. In the unitary model, every move matters and matters intensely.
The thing about most traditional wargames however is that every move doesn't matter, at least in the sense that the movement of an individual counter into this hex or that one isn't going to be a game-changer. Instead, wargames create meaning in aggregate - all the little moves of all the little pieces, taken together, create a shape, a line, a momentum, a game state.
But if someone comes into their first wargame with the idea that every move matters - and given that cultural depictions of games tend to lionize "one clever move that wins the game", it might even be kinda hard for someone not to - even if they click with the idea of moving "any, all, or none" of their units, they might be somewhat paralyzed by the need to make each unit's move count. All those units in front of them, it's too many options, too many possibilities. And of course it doesn't help the newbie to say things like "don't worry, wargames create meaning in aggregate" or "where you move each counter doesn't matter, it's where you've moved all of them together", and in fact makes things more inscrutable.
Despite popular myth to the contrary, there are newbies coming into the hobby all the time, who will gladly nudge all their counters as if it's the most natural thing in the world. It helps of course that many start as solo wargamers - I did - which gives them ample time to get used to the idea and to get over their anxiety. Every time we publish a hex-and-counter game, we get someone, somewhere, popping up to tell us that it's their first hex-and-counter game and how much they enjoyed it.
But I can't deny that other parts of the wargaming universe are expanding more quickly than hex-and-counter style games. There are in fact a number of self-described wargamers who have never felt the distinct sublime joy of consulting a Terrain Effects Chart to see if entering hex 2212 will cost them two movement points or three - who have never played a hex-and-counter game at all. Point-to-point CDGs have been popular since Mark Herman invented the form with We the People, while multiplayer asymmetrical wargames-with-wood-bits like the COIN series have many passionate fans. The broader appeal of these "non-traditional" wargames might have something to do with the use of euro-style mechanisms, playtimes, and presentation - certainly, that's what it's usually been chalked up to.
But I couldn't help but notice that all of these games follow some version of the unitary model. That is: in a CDG, you play a card, and that card generally lets you do one thing or activate one general. The COIN series, as I understand it, allows an acting/eligible player to perform one activity. My most popular wargames are Supply Lines of the American Revolution: The Northern Theater, 1775-1777 and Table Battles, and in both of those, last I checked, on your go you choose one stack or card and do one thing with it. If you're lucky and you're smart, on your go you do one clever thing with that stack or card.