Database corruption doesn't happen because of the number of cuncurrent connections... it comes down to how the database server locks the operation requests.
If the database is not properly configured, it can do update and delete operations to data that is being used elsewhere by some other cuncurrent connection. That causes corruption because the other connection is trying to work with data that doesn't exist anymore or was altered during that time.

Usually its not a big deal when you're on test environments, with only half a dozen people accessing the database it rarely or never happens that two people access the same data at the same time, but if you switch to a production system with hundreds or thousands of clients all accessing and altering the data it can happen that two or more try to alter the same data at the same time...