Fields
The tag can be controlled by Fields. To do so, enable the Use Fields option in the Basic Properties menu.
The Fields list can contain various position-dependent Fields. Imagine, for example, a Spherical Field that has a specific position. If the object to which the tag is assigned is deformed by a deformer/effector, or a simulation, for example, the position of the object points/clones, etc. will change. If the Spherical Field should affect the deformed or non-deformed element state, this is the option that should be used.
This option must be enabled if, for example, a character animated with joints (or elements of a matrix controlled by an effector) should move through the Spherical Field and the Spherical Field should take effect when the character passes through.
Especially when using clothing simulations, where vertex maps are often used to control the settings at point level, it is usually advisable to deactivate this option. If, for example, a vertex map controlled by a narrow Cube Field defines a tear line, this tear line should not slip when the fabric is moving. As a Cloth simulation is a deformation, this option should be deactivated.
See for example Field.