Back, when data plans were around 1GB or less some network providers didn't charge you for using whatsapp on specific plans in Europe. There were also whatsapp branded sim cards, but I haven't seem them for a long time though.

This can be very useful when you are learning programming.

You don't always have a tutor available and you shouldn't only rely on tutors.

It might be useful when you start learning a new programming language/framework, but you should learn on how to articulate a problem and search for solutions, e.g. going through stackoverflow posts and identify if the post applies and solves your problem.

After a while (took way too long for me) you realize that the best way to solve problems is by looking up the documentation/manpage of a project/programming language/whatever and really try to understand the problem at its core.