What is the disadvantage of using a dog leash snap swivel?

The choice indicating that a dog leash snap swivel can open on its own and weaken is correct because this type of clip may not have the same security features as other fastening mechanisms. In falconry, it’s crucial to ensure that the equipment, including leashes and swivels, is reliable since a bird's safety largely depends on the strength and integrity of its tethering system. If a snap swivel were to unexpectedly open, it could lead to an escape or a dangerous situation for the bird. Therefore, falconers often seek out more secure options that don't pose this risk.

The other options highlight different concerns. A swivel might or might not be heavy, depending on the specific design and materials used, but weight alone does not typically affect the bird's safety significantly. While providing too much movement could lead to less control over the bird, it's generally not considered a primary disadvantage of the snap swivel itself. Difficulty in attachment can also vary based on personal preference and experience, but again, this is not as critical a concern as the safety risk posed by a snap swivel that may inadvertently open.