I am trying to explain to you that achievement and reward are not the same thing.

Achievement is finishing a goal of some sort

reward is being able to experience the fruits of a particular goal.

You just give them endless achievements at no point do they get rewarded.

my car example is simple. they get the achievement of finishing the goal (completing the restoration) but they never get the reward (being able to drive the car)

Al they ever do is struggle to get to the achievement and they truly never get rewarded for that. You can't say "but you finished blah ad have done blah a dozen times already" that is the point if all you do is struggle every day to get to something it is not a reward. It is an achievement for sure, but never being able to take in it and experience the after effect of hitting that goal you never feel rewarded

another example since the car didn;t make sense to you ( I doubt this will since you feel the words mean the same thing) But, i'll give it a shot.

Somebody wants a pool in their backyard. They dig a hole gets some cement, clay, marble and rocks to put in that hole to a nice fancy swimming pool. It is finished after coming in daily for a few weeks to do all the hard labor. They go "WOO, i finished it, it was rough but i have a nice feeling of accomplishment" But right as they are about to swim someone backs a dumptruck back up to it, fills the pool with dirt rocks and such then drives over it with a steam roller compacting it all down.