Because that takes time and effort and this is relatively new.
HN user
alexboots
They forgot an important aspect of UI design: important info is never perceived as clutter by the user (from some page in 'Don't make me think')
But you are much more likely to pay for HBO if all your friends watch it and talk about the shows.
I work on projects on a pretty small scale (5 website, 1 or 2 of them need changes at a time -- some of them have 30 tickets, some have 3 or 4) and trello is perfect for me. If I fullscreen it I can get a good 'at a glance' look at everything i'm working on, and I have a colour code I use on labels to set the importance on projects.
I feel like trello has a certain tipping point for tickets :: at a certain point, its causes inefficiency. That being said, I felt pivotal tracker to be a bit lumbersome for my needs. I had to think too much / navigate the ticketing system.
I'd like to ask people who have used pivotal what thought think of it?
I haven't used Asana, but will check it out.