eli5: Why are there “silent letters” in words if they’re not meant to be pronounced? E.g. Why spell it “plumber” instead of “plummer”?

Question

This is true for a lot of words and I don’t understand what the point of including letters if they’re not supposed to be pronounced.

In: 6

Answer 1

Others has answered why the English and French languages has silent letters.

But there are many languages that developed similiarly, and they don’t have/rarely have silent letters, like Hungarian and Slovakian.

For us, there is a letter for every sound you make in the language, and (almost) every word is writtes as it sounds.

But the question is why did some languages did what the English did, that their writing is nothing like their speech?

I heard an anecdote, that in the medievel times, French and English book copiers were paid money/letter, so they added almost random letters to most words, so they would get paid more.
Or the English and French writers were so bad at grammar, that they often made mistaken, and later their version of the words would be used, until someone else was very bad at grammar, and the cycle continued.