That was my point - to show there's no correlation for the speakers to sales and to show how unimportant they are in the market, yet people keep going on and on about front facing speakers, as if they're some incredibly important feature - they're really not.
They definitely do not seem important from a company's perspective, which is driven by the bottom line. But I would argue that they could be important to the consumers and their overall enjoyment of the device. There are more factors than any single feature or lack thereof that go into a purchase decision, and most of them are based on marketing perceptions - not analysis. And several examples could be listed of features that are discovered after the purchase that are just barely not disappointing enough to warrant the consumer going through the hassle of a return. Companies could very well be doing the right thing by adding this or that feature from the perspective of the user's experiences and there are numerous ways that could never impact the company's profitability in any short-term sense. The overall experience surely does impact the retention rate from one purchase to the next, but probably not as much as things such as marketing, brand recognition and other things like price and timing.
Every company has to weigh up what's useful, what's not so useful and what will provide the most benefits for most users. Unfortunately, it seems that front facing speakers have fallen to the wayside.
Companies are definitely not making these decisions in a vacuum but they are making these decisions based on criteria other than "what is ideal". There are definitely going to be considerations, such as cost and engineering constraints. But here's the position that I find HTC in:
Premise: We want to add a Fingerprint Scanner
Setting: Our sales have sucked more than they've ever sucked before. We laid off most of our design team and about a quarter of our engineers. Deadline is approaching, we need to put something out. Everyone hated our last two original designs. Let's look at what the leader's are doing.
Observation: The two companies with the largest sales have the FPS on the front and on a home button.
Subconscious observation: We cannot design our way out of a wet paper bag, we better copy the leaders - and we've heard that Moto is going to put it on the front too.
Methodology: Copy, copy, copy
Observation: Oh shoot, where are we going to put the speaker? Oh well, put it somewhere else. The two companies with the largest sales have the speakers pointing down. Let's do that.
Methodology: Copy, copy, copy
Future observation: Wait, our phone was EXACTLY like theirs. Why didn't we sell any?
Subconscious observation: WHY DON'T THEY LIKE US!?