Unless trained and coached in Lean principles, many people new to Agile, and specifically to Lean, do not get work in process (WIP) limits and don’t see inventory as waste in knowledge work.
We have found it helpful to remind them of when their boss gave them too many things to do at once and the whole pile took longer to do. This leads to a discussion about context switching waste, and if they are open to it, they start to understand the theory of WIP limits. Then they get on the Kanban board, and from habit, they take 11 work item cards and drag them into their in process column on the Kanban board.
We have found it takes a week or two of noticing cards in WIP columns instead of queue columns and giving reminders to the team before teams new to Lean-Agile get this down. Coaching during daily standup meetings is needed. Telling them once or having them read about the principle once does not get it into practice on a daily basis.
Similarly, knowledge workers don’t seem to see inventory as a waste. This has to be demonstrated with an activity or demonstrated on their Kanban board. You can also use examples of other types of work they may be familiar with, like another department that centralized a particular service and then the entire workflow slowed down for everyone.
When you see the board like this, you have to tell them to put the cards back into the ready queue prior to that process step.
These messages need to be repeated like you are marketing chewing gum or some other product until you have mindshare of the team.