The part of the dock that moves every time the lake does, and the part most often ignored until it will not.
A gangway is a fixed length spanning a distance that changes with the lake. When the water drops, the same span has to cover more vertical, so the slope steepens. A gangway that is comfortable in June can be genuinely difficult in February, and the hardware at both ends is working at an angle it was not set at.
Every inch the lake moves is absorbed by the hinge at the top and the rollers or slide at the bottom. Those components see continuous small movement across the year, and they are almost always the first thing on a dock to seize, wear a groove, or come out of alignment.
When a roller seizes, the gangway stops sliding and starts pushing. That force has to go somewhere, and it goes into the floating section and its connections. Several dock repairs that present as framing problems started as a gangway that stopped moving freely.
Worth attending to before the next drawdown. A gangway that binds transmits force into the floating dock instead of sliding, and that force is what damages the connections it is attached to.