Weight and volume measurements cannot simply be converted 1 to 1 since matter, in our case ingredients have a different density. Meaning that temperature and pressure have a strong influence on volume measurements. However, quantities in recipes are rather recommendations of the author than absolute.
Caution on ingredients in small quantities (pinch, rotate, TL, …). Their fluctuations are more serious than with high-dose ingredients. Therefore, an extra teaspoon of salt might spoil your soup, but an extra teaspoon of flour in the cake is rarely insignificant.