This called it second round interview, or

To a sports fan, a playoff. They may have other candidates, who are as brilliant as you and who scored high mark after their presentation and QA section. Hiring is similar to screening. The pharmaceutical industry can screen millions of compounds on the priliminary screen. Those compounds which pass the first round will undergo other more stringent tests since a lot of false positive results were mixed with other real hits. Such screening might last several round until the scientists are sure they find the right one.

Until you get the written offer, keep fighting! You don't know who are your competittors. Take your best shot. Prove to them you are the ONE.

One muggle