diff --git a/development-workflow.md b/development-workflow.md
index 4118537..6fb5c78 100644
--- a/development-workflow.md
+++ b/development-workflow.md
@@ -2,7 +2,6 @@
 
 ### Ticket lifecycle
 
-* Any ticket that doesn't have a milestone is part of the backlog
 * Some tickets get assigned to milestones
 * Some tickets in the current milestone are given high priority
 * High-priority tickets are eligible to be worked on
@@ -21,7 +20,7 @@
 * No priority label: we haven't decided whether to work on this ticket
 * `Low priority`: the ticket will be worked on eventually but doesn't have a milestone
 * `Medium priority`: the ticket has a milestone
-* `High priority`: the ticket belongs to the current milestone and should be worked on immediately
+* `High priority`: the ticket belongs to the current milestone and can be worked on immediately
 
 ### Categories
 
@@ -32,6 +31,7 @@
   * `Task`: work that isn't visible to the user, e.g. refactoring or research
   * `Document`: work that produces a document
   * `UX design`: work that produces a design mockup
+* Before assigning the `UX design` label, ask yourself whether the ticket can be closed when a mockup is produced. If the answer is yes, assign the label. If the answer is no, create a child ticket for the mockup and assign the label to the child.
 
 ### Resolutions