Direct fingering--playing adjacent fingers on adjacent keys, extending the hand position to reach non-adjacent keys, or compressing the hand position without using one of the other fingering techniques--is the most economical of all fingering techniques. It requires less energy of the hand than any of the others, since no twisting or extra motions are required. It allows for pre-location of each finger over the next key to be played, promoting accuracy and rhythmic control.
Whenever possible, direct fingering is the best choice. Maximize the amount of time you spend in direct fingering. Modern scale fingering, for example, uses occasional crossings in order to allow three of four notes at a time to be played with direct fingering. This allows for rapid, accurate, and relaxed performance.