The below is a real life example. Due to the poor IP addressing, you will see wrong OSPF summary routing has been added in the routing table under specific condition.
As RFC 2328 suggests,the metric for summary routes in which the component of the summary route with the maximum / largest metric would determine the metric of the summary.
On Router 1, you will see the two routing entries for 10.16.192.0/23 have been added into routing table.
FYI:Route summary metric in RFC 1583
Area border routers then summarize the area contents (for distribution to the backbone) by advertising a single route for each address range. The cost of the route is the minimum cost to any of the networks falling in the specified range.