Orchestras are difficult.
One reason is that we’re really good at noticing when they’re out of tune. Just a tiny bit off changes our perception of the sound.
The other reason is that if the performers wait for a leader in their section to go first, every entrance and every attack will be muddled. You need to go when it’s time to go, not wait to follow closely behind.
Coordinating our tone and our tempo creates magic, and yet we often fail to lead, preferring to follow instead.