Most database companies would be proud to say that their products perform optimally out of the box. It means they accomplished a Herculean feat of engineering. But most databases have configuration options because this is almost impossible. For example, MySQL has scores of tuning options, and it needs a lot more.
So when someone benchmarks your database and makes you look bad, usually you can say “that benchmark was run by someone who doesn’t know how to properly tune my database software.”