As Joseph's rightly mentions in his contribution in the discussion, this is a form of "offshore" manufacturing where the goods are imported to Mexico, assembled, then, exported again, without paying any import/export duties.
The key point of this is to exploit the lower wages and manufacturing costs on the Mexican side without paying import and export duties.
It is known as "in-bond manufacturing" because the cross-border manufacturing facilities are a kind of "bonded warehouse" where the goods are not considered to have been imported as long as they are exported again after manufacture.
There are several ways to describe maquiladoras/maquilas, and they are often referred to as "sweatshops" in certain situations, but here, "maquilado" is a technical term, which is why I think "manufactured in bond" works fine.

If the products manufactured in bond are not exported, but cleared for home consumption, import duty is leviable on the quantity of imported goods contained in the waste.
http://www.iiem.com/em/export_documentation/chapter6.html

In Mexico, a maquiladora (Spanish pronunciation: [makilaˈðoɾa]) or maquila (IPA: [maˈkila])[1] is a manufacturing operation, where factories import certain material and equipment on a duty-free and tariff-free basis for assembly, processing, or manufacturing and then export the assembled, processed and/or manufactured products, sometimes back to the raw materials' country of origin.
[1] Also referred to as a "twin plant", or "in-bond" industry.[citation needed]
https://en.wikipedia.org/wiki/Maquiladora

When is a Customs bond usually required?

A customs surety bond is a contract used for guaranteeing that a specific obligation will be fulfilled between customs and an importer for any given import transaction. The main purpose of a customs bond is to ensure that the payment of import duties, taxes and fees owe to the federal government will be paid.
https://help.cbp.gov/app/answers/detail/a_id/734/related/1