For many years I've noticed that people I know would say they'll help me out when I need as I have done for them. It never happens, although I've thrown it out to them.
Neighbors say they'll give me vegetables from their garden like I had given to them when I had my garden; but due to an unfortunate accident I had, I couldn't do any planting. I desperately needed some of the veggies but they never brought me any. They knew I was injured but did not even offer anything.

I can't help but wonder why people do this.

Are they forgetful or they no longer care about others/their neighbors?

Have you experienced anything like this or similar?