What usually happen to sharecroppers who did not make enough money from their crops ro pay expenses?

they had to stay on the land until they could pay

Once the sharecropper was in debt, they were tied to the land and to the landowners for many years, they were also forced to sign exploitative or labor contracts that were favorable to the landowner.

It was not uncommon for a sharecropper to not make nought money because some landowners saw this as an opportunity to take advantage of the sharecropper.