Here is how you can minimise risks of failing imports:
launching one import then wait “enough” time for the import to complete.
avoiding multiple users doing imports at the same time.
running your imports when there is little activity in the system (to avoid the imports process running into database entities locked by other user actions).
These recommendations are mostly applicable for customers who have busy Prod Test environments with multiple users trying to complete various actions, including multiple concurrent imports.
The whole Study Design Import is done in one database transaction. This transaction is a long-living transaction that can keep locks on various Database Records/Tables, in case there is a need to roll-back due to a failed import.
This makes the import process an operation prone to lock timeout/deadlock problems with other transactions resulting from the activity of other users interacting with the system at the same time.