set your sights high/low
set (one's) sights high
To have very high expectations or ambitions. You have to set your sights high if you want to have a fulfilling life. We had a really great year for sales; now let's set our sights even higher!
set (one's) sights low
To have low expectations or ambitions. My brother's attitude is that, if you set your sights low, you won't be disappointed by life.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
set your sights ˈhigh/ˈlowbe ambitious/not ambitious; expect a lot/little from your life: If you set your sights high, you could do anything.
Farlex Partner Idioms Dictionary © Farlex 2017