Did you ever push on a door that’s pull only or the other way around? How did that make you feel? Probably not great, but I have good news: It’s not your fault! They’re designed badly.
A door should have a push plate or a pull handle, signifiers which clearly indicate what actions are possible without you having to stop and read the signs.
Don Norman talks about human psychology in interacting with objects or machines, the principles of discoverability, of feedback and affordances, signifiers, mapping, and conceptual models. Those all work together to create delightful, natural user experiences.
This book has changed how I look at objects and UI design forever, making me appreciate good design and notice bad design everywhere I go. It’s a classic and will be relevant as long as humans interact with objects.
I cannot recommend this book enough if you care about design at all.