WHY do the Germans read numbers backwards?

Arabic numerals became common in written German by the end of the 15th century. It was suggested that they be read from left to right. When there were no numbers, the Germans always wrote units first (one dash for 1, two dashes for 2), and then tens (X - 10).

For instance, the notation IXX used to mean "one and twenty."

The Germans retain this peculiarity. Previously, writers and mathematicians were constantly pointing out the issue of distorted number transmission. But all of their efforts to do anything about it were thwarted from on high.