Of course the most difficult thing on the violin is always intonation. The second one is rhythm. If you play in tune, in time with a good sound that's already high level. Those three are the main things.
-- Ruggiero Ricci
   
Ruggiero Ricci   Name:
Ruggiero Ricci
Type:
Musician
Nationality:
American
Birth:
July 24, 1918
https://www.nutquote.com/quote/Ruggiero_Ricci