A 1-to-1 teacher can lay out the learning methods for your personal situation, making it easier for him to organize his teaching.
And it's easy to lose track of the teacher if you have a big piano class.
Expansion:
The piano (Italian: pianoforte) is a keyboard instrument in Western classical music, and is known as the "king of instruments". By 88 keys (52 white keys, 36 black keys) and metal strings soundboard composition. The Italian Bartolomeo Christofori (1655-1731) invented the piano in 1709.
The range of the piano is from A2 (27.5 Hz) to C5 (4186 Hz), which includes almost all the musical notes in the musical system, and it is the instrument with the widest range except the pipe organ. Pianos are commonly used for solo, recital, and accompaniment performances.