The Effect of bevel differs between seemingly the same objects...why...

Hello. Thank you for watching.

I’m modeling an object and I’m facing a problem right now.

I want to bevel an object to make a zigzag face. However, when I press ctrl B and bevel it, the size of the meshes are different among them. I don’t know why this happens. I tried it with a different object which is mostly similar to the last one, then it worked evenly.

I’d appreciate if you could tell me why this happens. I’m confused very much…
bevel.blend (478 KB)

Look at the scale value of each object

Apply the scale with Ctrl+A (to reset the scale for each axis back to 1) in object mode, then bevel

Woooooow, Thank you very much!
I’ve heard that applying scal,location and rotation was important. But I didn’t know that not applying affects the result in this way… complicated trap for me.