SQL Shared Cursors, HASH_MATCH_FAILED

O have my database  set to cursor_sharing=FORCE  and this is an Real time OLAP database that executes the same SQL  starement with different values millions of times a day.

When I look at v$sql_cursor_sharing the column HASH_MATCH_FAILED has a Y in  85% of the rows.   I cannot find much info on this column and what it really means

I am trying to verify cursors are being reused (few Hard Parses) instead of  new cursors for each SQL statements.

Any insight into what the HASH_MATCH_FAILED really means would be helpful.

Thanks,