What is the motivation of this change? From the user's perspective, it seems illogical.
It makes bot / automated votes > users organic votes. No user can compete with bots and put vote early enough to get good curation reward.
Currently, the best reward is when we vote, say, between 5 and 10 minutes. I don't think it is currently a big deal with users voting too early then and "losing" curation reward.
I've read post from forum and this sentence below is definitely not true:
(...), they just lose curation by voting earlier than 15 mins.
They may lose, they may gain. It all depends. It depends on sum of rshares before our vote, sum of rshares of our vote, time of vote and total sum of rshares after payout. But for most users in most cases the best time to vote is between 5-10. And the smaller the vote the more profitable is to vote earlier. On the other hand whales should vote at the end of the curation window.
To give a better picture, it may look like this.
@jacekw @cardboard currently the UX is terrible for users who know about the 15 mins reverse auction window, leaves a heavy cognitive load and people second guessing if they should wait to vote and often even forget to come back and vote. It also isn’t conducive to short form content and the flow of discussion. There is a small tradeoff for that with bots being able to vote sooner, but overall it means the user gets more curation and helps get the content out of superlinear to linear faster. Also there is so much content now on Steem that the bots will serve to vote on established authors and helping retain them while human users can scout for new or first time users and will overall enhance curation.