The reconfigure command currently has no effect; it is included to allow existing scripts to run without modification. In earlier version, reconfigure was required after sp_configure to implement new configuration parameter settings.
reconfigure
If you have scripts that include reconfigure,
change them at your earliest convenience. Although reconfigure is
included in this version, it may not continue to be supported in
subsequent versions.
ANSI SQL – Compliance level: Transact-SQL extension.
reconfigure permission defaults to System Administrators and is not transferable.
System procedures sp_configure