I agree with this. I have found it frustrating to see someone scaling back the percentage of their vote. We are talking cents on the steem backed dollar here and my posts are genuinely of benefit to the steemit community!
I stopped auto upvoting my content because of concerns like this and it's something that I might rethink about implementing.
I often scale back the percentage, not to retain my voting power but simply because I think the post doesn't really deserve a 100% upvote. Particularly in the comments field, giving a 100% upvote may really propel a post from the bottom to the top.
That's fine, I agree with that. And what you think might be valuable, might not be what I consider valuable and vice versa. It my focus has been on helping new people bypass the mistake that I made. I would think that that sort of thing would have rated a lot higher. Shrug but it's subjective.
This is a good point. I nearly always give 100% for a post these days, but on comments I am more measured. It does irk me when a poor comment gets bumped to the top.