When installing the Agent Client Collector on a Windows machine, if you don't select an existent Service Account, ACC will install a default Service Account "servicenow".
This will be a standard Service Account and will not have the "PasswordNeverExpires" checked.
This means this Service Account can have its account/password expired in the future and this could affect the Agent Client Collector currently installed.
This is expected and ServiceNow decided to not create this Service Account with the "PasswordNeverExpires" checked as this could be blocked by strict security policies.
The recommendation is to either create the local account with the proper access (as part of the package distribution, for example) or use a gMSA account in AD, or change the "PasswordNeverExpires" from the default servicenow account later.
If you think this needs to be changed, there's an Enhancement Request (Idea) from our Community Portal:
"Agent Client Collector installation on Windows with the default service account that never expires."
You can simply vote for getting visibility and possibly be implemented in the future.