Why do foregin companies build plants in mexico

I have a question for the question you just asked.
Now, is this a opinion answer or is it supposed to have a one true answer?

Edit

Cheap production and labor costs, tax incentives and a relatively good transportation infrastructure into the end market (the United States) are the main factors.

Water flows along the east coast and across the western tropical pacific towards south america, while they both are directed towards that way,  el niño does not directly affect the southern flow of water along the coast.