At termination of membership, do not delete the Member from your list of members as this will most likely lead to ‘broken links’ and thereby creating holes in your historic club data.
Competitions contain references to Members. Deleting a Member can lead to side-effects as these reference do not link to well-defined data anymore.
(The same holds for Invoices; these have a reference to a Member as well.)
Rather than deleting a Member, assign a special category to the Member (like ‘terminated’). By doing so, you safely keep all historic data of your sports club. A true asset, while time passes!