A multi-point lock is not a collection of independent locking points. It is a coordinated mechanical system. When the strike plates do not match the lock geometry, the gearbox absorbs the error, users force the handle, seals compress unevenly, and an expensive door assembly begins failing from day one.
Cold climate lock failures rarely start with the key cylinder. They start with lazy material choices, dirty lubrication assumptions, chloride exposure, seal compression drift, and multipoint hardware that was approved in a warm sample room instead of a real winter assembly.
A hardheaded guide to choosing lockcase structures for high-security door systems, composed for door brand names, makers, job purchasers, and protection hardware groups that do not desire advertising and marketing language concealing mechanical weakness.
Most multi point lock failures in aluminum doors do not start with burglars. They start with lazy geometry, weak material pairing, bad keeper alignment, and specs written by people who care more about finish samples than cycle life. Here is how I would engineer the system so it survives real use.
Most buyers still compare multi point locks by unit price, which is exactly how they get trapped in higher lifetime cost. I make the case for serviceable hardware, standardized parts, and maintenance-first specification using recent public-sector evidence.