It's not hard to understand that if you take a bite of an apple and let it sit for a day that it will become brown.
It's not hard to understand that if you get on a plane from Chicago to London that you will end up in London.
We have no issues understanding how our past decisions make up our present reality if the action translates into something we can witness.
But it is much harder for us to conceptualize something more abstract that may not have a physical outcome.
Regardless of what you may think, all of your thoughts and actions have consequences.
No matter what.
You may not see them, but they are there, silently paving a road for your future self to walk on.