The mind is designed for survival, not our evolution and progress. Change causes uncertainty and therefore a threat.
Our short-term satisfaction
Instant gratification is a barrier to change. change requires time, effort, sacrifice, patience, persistence, hard work to reach our long-term satisfaction.
The force of habit
We feel the need to stay consistent with our identity, that is, with who we are until now. Change on the other hand leads to the change of this identity, therefore to the inconsistency of our original identity.