Looks nice, but was sorely disappointed there was no self hosting option. I would be very interested if I could keep my data on my servers, but cannot move to this otherwise.
Confidentiality and security. Sharing that level of information with outside organizations is just not possible in some situations. Regulated industries need to have full auditable control of all of their data and infrastructure, and a third party does not allow for that.
Even if it was possible for me, I still would not want that level of information out there with a third party. It increases the surface area for an attack, and puts the company at greater risk relying on an unknown level of security which there is no direct control over.
Perfectly put. I would also add that the SaaS market has shown enough volatility that if I can't run it on my own instance there are no guarantees that a service will exist a year from now.
When it comes to my personal todo list, I'm ok with that. When we're talking about a project management tool that becomes a part of your team's culture, concerns mount quickly.