Mindfulness of Watching Youtube

I noticed that upon watching Youtube videos, I seem to become sucked into merely watching stuff online. I almost 'forget' to do other things. Oddly, this doesn't happen while reading online, or creating something. **Can one directly relate this to lack of mindfulness? Is any such instance of 'forgetting' usually linked with mindfulness?** More so, **why might reading not generate this type of absorbed state?** Thank you