Question

why all minerals are ores

Answer 1

THe question seems wrong . It should be that Why all minerals are not ores ?
Those substances which occurs naturally in the Earth's crust are called Minerals .And minerals which can be extracted from the Earth's crust profitably is called ores . Therefore all ores are minerals . Metals with high concentration can be acheived profitably but  not all minerals. Therefore all minerals are not ores. 

Answer 2

All ore are mineral but all minerals are not ore because An ore is a type of rock that contains minerals with important elements including metals. The ores are extracted through mining; these are then refined to extract the valuable element(s)