An investigation into reasons of why contemporary art pieces are usually sold using the “English auction” method, as opposed, for example, to some form of “sealed bid” auction.

When, in November 2018, David Hockneys "Portrait of an Artist (Pool with two figures)" is auctioned at Christies, it is likely to reach a world-record price for a work by a living artist. Why such artwork is usually sold using the "English auction" method (as opposed – for example – to some form of "sealed bid" auction)?