There have been rumors circulating for quite some time that Intel (NASDAQ:INTC) might have won a place in a future Apple (NASDAQ:AAPL) iPhone. Indeed, one analyst actually went ahead and jumped the gun, predicting just ahead of the launch of the iPhone 6s/6s Plus that Intel would be in no fewer than half of the latest generation iPhones that hit the market.

Of course, it became immediately clear once Apple published additional details of the devices, that Intel wasn't involved. Bummer for Intel stockholders.

But a report from Fudzilla a little while ago suggested that Apple would be using an Intel modem inside of its upcoming 4-inch iPhone refresh. This, as I wrote last month, seems quite believable.

In this article, though, I put forth the following argument: It wouldn't just be nice for Intel to win this spot, it's practically necessary in order for investors to take the company's modem efforts seriously. Here's why.

No major wins thus far
Intel completed its acquisition of the assets of struggling Infineon Wireless in early 2011. The goal here was to buy this "fast follower" in the world of cellular modems and, with major financial backing, transform it into a leading vendor of such chips.

Of course, such major investments take time and it would not have been reasonable for the company to deliver anything resembling "leadership" parts in 2012 or even in 2013. However, I would have expected the company to start making some real (financial) progress by the time it rolled out its (highly touted) second-generation multimode LTE solution known as the XMM 7260.

The XMM 7260 won a few smartphone designs, but to my knowledge, it didn't ultimately amount to much financially for the company.

To make matters worse, I believe the gap between Intel's modem technology and what Qualcomm and even Samsung (NASDAQOTH: SSNLF) are fielding has actually widened rather than shrunken along a number of critical vectors.

An iPhone win would validate Intel's long struggle
By far the highest profile customer of stand-alone modem solutions is Apple; most other smartphone vendors tend to favor integrated one-chip modem and applications processor solutions for space/power reasons.

This means that the only worthwhile, high volume customer for Intel's stand-alone modems is Apple.

Yes, one could argue that stand-alone modems are useful in other applications (laptops, Internet of Things, premium 2-in-1 devices), and one could even argue that Intel's modem investment pays dividends in ultimately enabling the company to build its own single-chip applications processor and modem solutions for phones.

However, if Intel's modems aren't good enough to win a spot at Apple -- which, frankly, would probably love a second source for its stand-alone modems so as not to be completely beholden to Qualcomm -- then why would they be good enough -- either in stand-alone form or integrated with applications processors -- for other smartphone makers who already have multiple viable choices in the form of Qualcomm's solutions as well as MediaTek's?

Running out of patience with Intel's modem teams
If Intel is able to win the upcoming smaller iPhone, then such a development should give the investment community confidence that Intel isn't just spending money on modem development with nothing to show for it.

That said, this is a marathon and not a sprint, so even if Intel wins the iPhone 6c, it will need to continue to develop technology at a sufficiently rapid enough clip to continue to win future iPhones while further expanding its client base.

It's not going to be easy for the chip giant, that much is clear. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.