What's the most frustrating part of delivering client work today?

I built Iris because I kept running into the same wall: you spend weeks on a project, send a link, and then have no idea what the client actually looked at or what they meant by their feedback.

Curious what others experience on the delivery side. Is it the vague feedback? The lack of visibility after you send? The fact that clients open a Dropbox link on their phone and lose all context?

Would love to hear what actually frustrates you most about how client delivery works today. Building this product in the open and every answer genuinely shapes what we build next.