Curation is one of the important parts of Steemit, where one can earn the reward by curating on other posts. Curation means upvoting on any post i.e putting your upvote value and appreciating the good work. The curator in return will get part of 25% of the post’s total pay-out i.e after 7 days.
Nowadays, I have noticed, many “Curation Trail” are in offering to upvote on the posts.
Curation trail is the automated voting set up of the trail of upvotes which follow an account and flows according to it. It is kind of delegating your voting rights to someone. By being part of the upvote trail, the user becomes the part of the account and follows them, and whosoever post the account upvote, you will also upvote the post automatically through curation trail
Currently on Steemit, “Steemauto” helps any user to set up an auto upvote on any author of their choice, or be part of the upvote trail by being part of the curation trail of a particular account. The user can also create their own curation trail.
For example
I want to be a part of upvote trail on 
Steemauto gives you the flexibility or the option to set up your own voting weight on the curation trail i.e as per your choice of the voting percentage that you want to apply on the trail. Be it 1% or 100 % the choice is completely on users. Once fixed the same voting percentage will apply to all upvotes.
The automation of curation upvotes does have some “Pros” and “Cons”. Let’s have some insights that I have observed by being part of the trail lately.
It avoids the manual curation on the post, as it is automatic upvote system.
Curation trail is boon for the inactive accounts holder. These accounts are not active regularly and their upvotes get wasted. Through Curation trail they get chance to curate good post and earn some rewards.
You do not need to bother or wait for publishing the post. Being and automatic upvote option, the curation upvote applies to the post by setting the upvote timing from the posting time of the post.
It is an automatic source of earning curation rewards by following curation trail of high earning authors.
Draining of the “Voting Power”, As the user is not aware of the number of posts that the account follows. Accordingly, there are chances that the VP gets drained quickly.
The advantages of reading the post and interaction with the user through comments will not be there on the post, thereafter you might loose on follower and following or even reading some of the good post/contents.
The curation upvote may be gone to some post/contents in which you might not be wanted to upvote, or it is not of your choices like some shit posts or nsfw contents.
You are not able to curate much by yourself on the post of your likings due to low Voting Power.
Steemit is the blogger's paradise with emphasis on user interaction to grow. Comments are the best way to interact or discuss any topic. I believe, the curation trail is putting the objective in danger. Through auto upvote, the user is unable to interact much with each other and get a healthy discussion.
Before opting for any such curation trail, make sure to analyze the trail that you are delegating your voting rights. Also, once you registered you do not get many chances of upvoting manually on your favorite posts, due to lack of much voting weight. So, make sure you are not in habit of upvoting on other posts.
Curation trail is best of use when you do not want to curate manually.
@steemflow