darrenforster99 speculates as to the reason forusing Torx head screws, and thinks it started out as a security thing. Actually, no, it wasn't anything to do with security. If you want security, there are better screw designs readily available.
Torx head screws have two major benefits in manufacturing. (1) They can take more torque than standard phillips head screws, allowing machinery to tighten things down with a bit more power, and reducing waste from either heavy handed assemblers, or over-strong robots stripping out the heads. (2) The screwdriver doesn't slip out as easily as a phillips head, making it more reliable for automated assembly. In short, when you are putting a lot of screws in with automated, or semi-automated human assisted machinery, Torx head screws reduce your costs by being more reliable on the assembly line.

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