Roku (ROKU 0.35%) has had a difficult 2022 to say the least. After posting 56% revenue growth in 2021, the business has seen its sales gains shrink to just 12% in the most recent quarter. A softer digital ad market has also caused management to forecast a year-over-year revenue drop of 8% in the fourth quarter. And consequently, the stock is down 83% this year. 

If you're thinking about becoming a shareholder in this top streaming stock, there's one important factor you must consider. Let's take a closer look at what that is. 

Revenue sources 

Roku's business operates two different segments. The one that most investors are probably familiar with is called the Player segment, which includes sales of the company's media sticks. Five years ago, in Q3 2017, this segment represented 54% of overall revenue. In the most recent quarter (Q3 2022), this segment accounted for just 12% of company sales. 

Interestingly, the Player segment has been operating at a negative gross margin in the past six quarters. Supply chain issues and inflationary pressures have resulted in higher input costs that management has decided to insulate from consumers. It's a good strategy, as active accounts of 65.4 million are up 16% year over year. 

Roku's other moneymaker is the Platform segment, which includes revenue from advertising and subscription arrangements. This has generally been the fastest-growing part of Roku's business, even posting a 15% year-over-year sales jump in the latest quarter with gross margins exceeding 55% historically. It is expected that the Platform segment will drive the company going forward. 

Lack of negotiating power 

There is certainly value for both viewers and advertisers that use Roku. Viewers have access to a seemingly unlimited number of streaming services in one place, and companies looking to target them with ads have a connected-TV platform to do so. Roku's ecosystem has a real purpose. 

However, investors should consider Roku's negotiating leverage with its third stakeholder group -- content companies. Roku's typical agreement in its Platform segment is that it controls 30% of the ad inventory from content companies and keeps 100% of that revenue. Therefore, as more ad-supported services are offered, and more businesses find value in marketing in this ad ecosystem, Roku should benefit. 

Roku might be able to control deal terms with smaller and/or unprofitable streaming services, but with the larger ones, it's a different story. For example, about a year ago, Roku was in tense negotiations with Alphabet's YouTube and YouTube TV offerings about renewing their distribution agreement to keep the services on Roku's platform. Roku claims YouTube was demanding onerous terms, which the latter denied. 

Eventually, the two sides were able to work it out to viewers' benefit. But the highlight of this situation was that Roku doesn't share any ad inventory with YouTube, and therefore, it doesn't earn any revenue from Alphabet. Plus, it's probably a safe assumption that Roku needs YouTube for its long-term success more than the other way around. 

Netflix, the leader in the streaming market with 223 million subscribers, recently launched its own cheaper, ad-based membership option. I'd suspect that Netflix, like YouTube, won't supply any ad inventory to Roku, either. That's because Netflix is so dominant in the space and is about to start generating positive free cash flow on a sustainable basis. And this gives it leverage over Roku. 

The bull case for owning Roku stock centers on the business growing its Platform-segment revenue by attracting greater advertising spending to its ecosystem. But the issue that's now becoming evident is that Roku's potential is seriously capped if some of its biggest ad-sharing revenue opportunities, from the likes of YouTube and Netflix, which accounted for 16.4% of total TV viewing time in November in the U.S., are essentially paying nothing to Roku. 

I'll admit that I didn't fully appreciate this dynamic before. But now that I do, it creates another mental hurdle to clear before being comfortable owning the stock. For investors who are fine with this, Roku might still be a solid company to own.