There is zero shortage of places to watch digital video, but Comcast thinks you’d like some more. So here comes Watchable, the broadband and TV provider’s attempt to get in on an increasingly crowded market.

This is the platform industry observers have been tracking for more than a year. It will be ad-supported and free, and you can watch it on the Web via an iOS app or on your TV if you have one of Comcast’s newer X1 set-top boxes.

The fact that you can watch Watchable without being a Comcast subscriber is worth noting, since many people believe Comcast will end up trying to make real money outside its “footprint” of areas where it sells Internet and TV access.

And what will you see if you watch it? Web video — which you can see in many other places — from a few dozen outlets including BuzzFeed, Disney’s Maker Studios, Vice and Vox Media, which owns this website.

Comcast’s beta launch comes at the same time that Verizon is ramping up the rollout for Go90, its own video service, which is a lot like Comcast’s except that it has a smattering of exclusive content — though not nearly as much as Verizon is suggesting via its marketing — and Verizon wants you to watch it on your phone. That way Verizon can make money two ways: From ads as well as from the data charges you will theoretically rack up as you watch this stuff.

I’m all for experimenting, and there’s no reason for video makers (again, including the people who write my check) not to try these new platforms. But I’m skeptical that either will work.

That’s because both are premised on the idea that if you take a bunch of video and put it on a device people already use, they’ll want to look at it just because it’s there. It’s possible that this idea might have worked in the old days of TV, or even cellphones, when your viewing choices — let alone your entertainment choices — were pretty constrained. But that’s not the case now.

Meanwhile, this theory does work over at Facebook and Snapchat and, to some degree, YouTube. But those are places I go because I want to go, and the fact that someone’s serving up some random videos to me there is a bonus, not a reason to go there.

Put it another way: If assembling a bunch of videos, most of which you can see other places, and putting them on devices with a big installed base was a winning formula, then Samsung’s Milk Video product, which does just that, would be a big hit.

Milk Video, which launched last year, is closing next month.