there are different flours available which vary in suitability for different purposes and in cost. King Arthur Flour has a computer controlled mill and they offer a service to bread makers to let them specify their own "recipe" for the flour they wish to order.
https://www.cooksinfo.com/flour-grades
excerpt:
"French bakers will use straight flour in their bread making; North Americans and British generally don’t.
"Straight flour is separated by sifting in other grades. The straight flour is passed along a roller over different sieves. Different grades fall through the appropriate sieve along the roller. In the percentages given below, the lower the percentage of straight flour that falls through a particular grading sieve, the more desirable the flour."