In agile you do user stories, they are a kind of to-do items for developer instead of the traditional analysis and those stories are discarded after the work is done. Architecture on the other hand is design done after a long and solid analysis with the view to stay. Architecture is to translate into standards, guidelines, framework and governance all designed for the long haul.
Let’s take compliance as an example where we constantly will create many user stories to satisfy current requirements. The problem with this is that the requirements are constantly changing and the number of compliance initiatives is constantly on the raise. With this it is important to capture the general intent behind all the different initiatives and then build standards and frameworks that will support the intent. This will then make it easy to satisfy the requirements and also safeguard against a too high expenditure on compliance.
However for this to work the architects will require being transient or agile prove, so that they can focus on the longer term goals. The same is also true when investing in any other long term project where the year to year requirements are no clear from the start.