If you want to monetize your youtube well as 1,000 subscribers, you also need 4,000 hours of Watch Time on your videos over the last 12 months. There is some confusion with this one, so let me try and clarify that. First of all, this is not about how much video content you, the YouTube creator watch. This is all about how much video content is watched on your channel by people all across the world. It’s all those hours of video that people have watched on your channel in the last 12 months (from any given date). You could well have well 4,000 hours of Watch Time over the lifetime of your channel, but it's only the last 12 months that count for YouTube Partner Program requirements.
A couple of things to tell you about Watch Time. Live streams do count towards that total. Unlisted videos also count towards that total. But if you delete any videos, that Watch Time will be removed from your channel Watch Time hours. And one more final thing, if you are already in the YouTube Partner Program, and if your channel falls below 4,000 hours of Watch Time, YouTube won't automatically remove you from the partner program, but they can do it at their discretion