Why should Apple make their own iPhone parts?

Why should Apple make their own iPhone parts?

So they can say everything is theirs. And they own everything.

It makes the parts cheaper, if they bought the parts it would be the cost of the materials, plus the labor it took to get the materials, and then it moves on to the processing materials which adds the price of processing and the labor there, then assembly which is the cost of the assembly plus the labor there, and then apple has to buy it and you would pay all of that plus the price of labor and assembly of the phone itself (that is how most companies do it) but if apple makes their own parts they can make them more specially for their product and they cut the cost of the other company assembling it and that labor price, reducing the price of the product

To do so would make the cost of the iPhone insanely high, with little gain in product quality and a significant drop in profit.

Let's take an example of a common item - a toaster. Up until the latter 1960 and early 1970's, when a US company such as General Electric made a toaster, they also made all of the parts in that toaster. To pay $30 in 1960's money for a toaster was common. Imagine that in 2010 decade money. Today a toaster costs less than $20 - even less for a definite toss-a-way. A cell phone is a toss-a-way due to technology… It does not need to last for many years.

Turn that to a cell phone. To cut costs, a manufacturer simply has to outsource components to a company that can build them within a reasonable economies of scale. A few major electronic product makers do indeed build most of the parts within their products, Sanyo, Toshiba and Samsung come to mind here. But that is simply as they have also invested into parts manufacturing. If Apple made their own phones, with their own parts, a car would cost less to purchase.