I have picked up another interesting snippet from David Crystal’s book By Hook or by Crook: a journey in search of English (2007). English spelling does not match well with current pronunciation. As is well known, some such mismatches arose because English spelling began to stabilise before some major changes in the English sound system. One set of such changes is often called the Great Vowel Shift. https://languagemiscellany.com/2022/01/great-english-vowel-shift
Crystal’s book has just taught me about another cause of mismatches between spelling and pronunciation in English. After the Norman Conquest in 1066, French-trained scribes noticed that it is hard to read words containing the written vowel <u> next to such consonants as <i>, <v>, <n> or <m>. This is because in manuscripts such words contain a sequence of identical downstrokes.
To make these words more legible, these scribes replaced the character <u> with the character <o>. We now use the character <o> in words such as come, love, one and son, even though they contain the vowel usually written with the character <u>.
So, these French scribes made it easier to read manuscripts and other handwriting, but harder to learn English spelling.
For another post inspired by Crystal’s book, please see https://languagemiscellany.com/2022/07/that-welsh-place-with-the-long-name