Why do beginners keep losing pieces to the cannon?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
Because a cannon's danger is conditional in a way nothing in chess prepares you for. A rook or chariot aimed at your piece with a clear line is a threat right now. A cannon aimed at your piece with a clear line is not a threat at all, it needs exactly one piece in between to capture. Beginners either ignore cannons on open lines (correctly, until something moves onto the line) or panic about them constantly (incorrectly, when nothing is between).
The habit that fixes it
Before every move, for every enemy cannon aimed anywhere near your pieces, count exactly how many pieces sit between the cannon and the point it is aimed at. Zero, no threat yet. One, it can capture right now. Two or more, still no threat. This becomes automatic within a few dozen games, but it has to be done consciously at first. See how the cannon moves.
The classic way it happens
You move a piece onto a line an enemy cannon was already sitting on, intending to develop or defend, and the piece you just moved becomes the screen that lets the cannon capture something behind it, sometimes your own piece a rank further along. A move that looks purely constructive can silently load an enemy cannon.
Related questions
Does this get easier with practice?
Yes, quickly. Counting screens becomes automatic well before most other tactical skills do.
Is there a name for this kind of tactic?
Several cannon-based tactics have their own names; see cannon tactics for the common patterns once counting screens feels natural.
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