Leaving SmugMug...Inability to advertise to site.
I've asked, for a year now, for the ability to use standard digital advertising techniques, remarketing tags, etc. Without the ability to capture traffic on my site, serve them ads, etc. I've found myself losing business on my SmugMug site, only to have business increase on my services and portfolio site where I am able to deploy these techniques. The lack of communication is what bugged me the most.