You cannot make an omelet without breaking eggs

you can't make an omelet without breaking (a few) eggs

proverb Sometimes, you have to do unpleasant things in order to complete a task or meet a goal. Your students clearly don't respect you. I know you don't want to yell at them, but you can't make an omelet without breaking a few eggs. If I don't cut people's salaries, the company is going to go bankrupt. It's unfortunate, but you can't make an omelet without breaking eggs.
See also: breaking, egg, make, omelet, without
Farlex Dictionary of Idioms.

You cannot make an omelet without breaking eggs.

Prov. In order to get something good or useful, you must give up something else. Jill: Why do they have to tear down that beautiful old building to build an office park? Jane: You can't make an omelet without breaking eggs. Alan: We may make more money by raising our prices, but we'll also upset a lot of customers. Fred: You can't make an omelet without breaking eggs.
See also: breaking, cannot, egg, make, omelet, without
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

you can't make an omelette without breaking eggs

If you say you can't make an omelette without breaking eggs, you mean that it is impossible to achieve something important without there being some bad effects. Note: `Omelette' is usually spelled `omelet' in American English. You can't make an omelette without breaking eggs. If you want universal health care there's just no way of getting it without us putting more money into it. The group does appear to be setting new reporting standards but you can't make an omelette without breaking eggs.
See also: breaking, egg, make, omelette, without
Collins COBUILD Idioms Dictionary, 3rd ed.

you can’t make an ˌomelette without breaking ˈeggs

(saying) you cannot make an important change in something without causing problems for somebody: I know that all these changes in the industry are painful to many people, but you can’t make an omelette without breaking eggs.
See also: breaking, egg, make, omelette, without
Farlex Partner Idioms Dictionary
See also:
  • cart before the horse, don't put/set the
  • don't cry before you are hurt
  • a thing you don't want is dear at any price
  • don't give up the ship
  • don't bark if you can't bite
  • argue back
  • all in (one's) head
  • don't get me wrong
  • don't bet on it
  • don't beat a dead horse