When you are at A and you look forward you will see multiple paths. One way leading to B and the other way to another destiny. The future contains multiple choices and opportunities.
But when you are at B and look back you do not see multiple paths. You only see one rather straight path that connects B with A. And maybe you do not even reflect on the selection of path that actually made it possible to get to B.
Look forward and you see lots of opportunities and choices. Lots of decisions to make. Lots of paths! Magic!
Look back and it just seems very natural and obvious that you are where you are. A straight line. And it almost seems inevitable that you ended up where you right now are.