First you need to define what you mean by classical music. Depending on who you’re talking to that could be anything from Mozart or Bach in a group orchestral setting to something instrumental written in the last 5 years played solo, or any combination in-between.

I’m not an orchestral player, more a bluegrass and old-time musician, so take what I say with a grain of salt.

When you are playing in a group orchestra, you are not a musician. You are an instrument. The conductor is the musician. You’re there to play the notes on the page. The conductor may give you some leeway, may not.

In smaller groups, you may or may not have more freedom depending on the musical style and the group dynamics.

Solo, do as you please so long as it sounds good. You are both the instrument and the musician here.

As always, there is only one hard rule in music, If it sounds good, it is good. Everything else is just guidelines.