Why do people bother adopting cats/dogs if there going to surrened the next year?

[petsinformation]

This cat was adopted last year-it was 6year old called Kaycee, her original reason for being surrended was because her OWNER was moving, she also had a pair called Maxi, maxi was rehomed without her to a different family & i notice Poor Kaycee come back this week, and aparently the owners who adopted it NO longer wanted her. It is defiantly the same cat-new picture-to make her look like a different cat, however the shelter appear to forget that she was 6year old last year, when she now be a 7year old.

Why do people adopt a cat and then surrended it the following year and say the NO longer wanted it?

Why do people adopt a dog and then say they No longer want it?

Doesn't this make you sad.