You're incentivized to vote after 30 minutes. Within the first 30 minutes you pay a penalty, but after 30 minutes you keep all of your curation rewards.
You can't just vote anything, as you have very limited voting power. And you'll only earn good curation rewards on discovering good content and voting before larger stakeholders do.
Oops; I stand corrected! I had understood it when I joined Steem, then got confused by some discussions last week. Thanks for correcting me.
Downvoting a post can decrease pending rewards and make it less visible. Common reasons:
Submit