Because the two valve types are different they require two different types of head on a pump or as is often the case an interchangeable head.
Bicycle pump valve types.
Kitbest bike pump portable bicycle floor pump with glueless puncture kit mountain road bike tire pump mini bicycle air pump compatible with presta schrader valve and sports ball by kitbest 12 99 12.
A bicycle pump is a type of positive displacement air pump specifically designed for inflating bicycle tires it has a connection or adapter for use with one or both of the two most common types of valves used on bicycles schrader or presta a third type of valve called the dunlop or woods valve exists but tubes with these valves can be filled using a presta pump.
Presta valves were invented by the same guy who went on to found zéfal one of the leading bike pump manufacturers.
It is cheap but inefficient due to higher risk of air leaks through multiple joints.
There is minimal chance of air leaks making it more.
Several pump designs can handle presta valves including pumps dedicated solely to presta valves those with separate connectors for each type a unit with a reversible gasket that handles both valve types or one equipped with an adapter that converts from presta to schrader.