Why do factories like to install cell phone jammers?

I found that many factories like to install signal jammers, I would like to ask what is the specific reason?

Topsignaljammer  2022.3

The wide application of mobile phones is a double-edged sword. The benefits brought by mobile phones need not be described too much, but for some special places, the use of mobile phones should be restricted or even prohibited. In some special places, such as workshops, the use of mobile phones is restricted. According to the traditional list of rules and regulations, personnel supervision, and punishment systems, it is impossible to completely eradicate and eliminate the proliferation of mobile phones. At present, it is more feasible from the perspective of technical products. The method is to install a cell phone blocker or a mobile phone signal shielding system at an appropriate location in the factory area. Each mobile phone signal jammer can cover a certain area, and these coverage areas can be formed into an area of coverage in the form of a cellular network. Achieve complete signal shielding of large areas.