As an ex-Slack user, who is now using Microsoft Teams, here’s what I don’t like about using it:

  • There’s markdown support but it’s buggy and the editor gets confused.
  • It has a chunky, space wasting user interface, with no compact options.
  • You can delete channels but not archive them (there goes your organisational memory).
  • There’s no real equivalent to CTRL-K.
  • Chat and Teams are on different tabs so if you’re on one you can easily miss messages on the other.
  • You can’t configure notification settings on a per-channel basis.
  • You can’t quickly create a named channel with a fixed set of people without creating a “team” first.
  • There’s no notification configuration for key words being mentioned in a channel.
  • Only users within a group can view the channels, unlike Slack’s approach of transparency (anyone can view a channel if they want to).
  • If you have a short message and want to select the value in it, e.g. a story ID, you basically can’t, the “on hover” UI covers it up.
  • Some of the connectors aren’t as configurable or good as the Slack equivalents.
  • No slash commands.
  • The notification area icons for “In a meeting” and “you have a message” are the same.
  • The Giphy thumbnails are too small to read the text on them, and they’re all squashed to be square.

On the positive side - the integration with Outlook meetings, voice calls, and SharePoint is ok.