Creating effective maths worksheets

Worksheets have been used in maths classrooms for a long time, much before the pandemic. There are some resource groups that teachers can subscribe to, which periodically share worksheets on various topics over emails. Worksheets are related to workbooks: the note to textbook writers at the beginning of NCERT syllabus for classes I-V states categorically that the ‘class I and II books would be workbooks’. So, we can consider a workbook to be a collection of thoughtfully created and ordered worksheets. So, why are worksheets particularly popular in maths