Why do you have to prefer HTTPS over HTTP

[yyjh]

Let's Encrypt has done a big change to the internet, that is for sure. But the biggest problem of Let's Encrypt's certificates is that most normal people see that little green secure lock at the address bar, they tend to think the website is legit and without any problem. Let's Encrypt has issued a lot of certificates, but has done too little explaining https is not risk free.