It's because it compares two companies on the same ground.
Company A does sales of 1000 Cr and makes a profit of 100 Cr.
Company B does sales of 600 Cr and makes a profit of 80 Cr.
Even with lower sales and profit, Company B is more efficient in earning better per sales done.
This is the reason while comparing two companies, we should check for Margin numbers.
Where to get margin %?🤔
➡️ In Common Size Statement.
It is a statement whereby each line item is expressed as a percentage of revenue or sales in the income statement and by total assets on the balance sheet.
Don't worry. You don't have to calculate it manually.