As I've probably mentioned in this blog (and I've certainly said it in my podcast), I'm not very good at most wargames. It takes me longer to get a decent understanding of how to play than most people, I think. I've figured out one reason why this is the case--the CRT (Combat Results Table). The CRT is a staple of many wargames--usually you calculate the odds of an attack, roll a die (or dice) and cross-reference the roll with the appropriate odds column on the CRT to figure out what happens. Most results are fairly standard--units are damaged or eliminated, retreats, etc.
However, every game has a different CRT, and when learning a new game you need to actually study the CRT. Different CRTs can produce wildly different results. I tend to think all CRTs are like the classic Avalon Hill ones, like in The Russian Campaign, so I tend to play that way. Which often leads to bad results.
For example, the CRT in the excellent game A Victory Lost is pretty mild--even at high odds, most attacks don't directly damage or kill units. Instead, retreats are by far the most common result. Since eliminating units is a key way to earn victory points in that game, you really need to know that about the CRT and adjust your play accordingly. Other games have much deadlier CRTs, or ones that favor the attack or defense. I have a feeling if I studied CRTs more diligently, I'd probably be a little bit better at some of these games.