Adobe not my main ho. That means this shit wasn't sponsored by them. Thanks.
The cost of Photoshop has long been a huge meme, and piracy of the Adobe suite is (and always has been) rampant. After all, do you really expect that 15 year old making graphics for his Minecraft server to have ponied up $700 for the latest Photoshop?
Then along came Creative Cloud. Who would want to pay monthly for Photoshop, when they could pay once and use that version forever?
As with any software, you lose out on new features if you don't update. And you can't update if you don't pay more. With fairly frequent major releases, keeping up-to-date with Photoshop (and other Adobe suite applications) quickly becomes a costly endeavor.
But remember the question I posed 2.5 sentences ago? Who would want to pay monthly for Photoshop? Well, it turns out (as of the time of writing) you can pay $10 per month and get the latest version of Photoshop...