I certainly believe in upvoting your own posts and this opinion has been substantiated by the bees knees. But if you have better things to do with your votes then ensure you choose wisely.

Here is a legitimate reason not to upvote your own post but it is merely a recommendation for making best use of your votes.

https://steemit.com/upvote/@timcliff/opinion-why-you-shouldn-t-upvote-for-yourself