To head this off, never wait until the deadline to check on the deadline. Frequent check-in’s are key – how are they doing? Are they stuck? How can you help them succeed?
Daily standups is a technique used in Agile software development process that formalizes the check-in's. Every day at the same time, the team would get together in a standup meeting lasting 15 minutes or less, and they share what they did yesterday, what will they do today and where do they need help. It is a great way to prevent expectation mismatch – if things are slipping you will catch them early.
If you are checking all the boxes on Agile rituals and you are still missing all of your deadlines, you should sit down with the developers and discuss what is going on. Are the deadlines unrealistic? Are the goals not clearly articulated? Is there misunderstanding about the work scope? Is the team not disciplined in breaking down work into smaller batches? Is a research task mislabelled as a development task? Is the team prone to writing code without designing the architecture first and having to deal with a lot of rework?
Find the root cause of the slippage, then collaboratively find a way to address the issue.