Agents and tasks rationale

After digging into and experimenting with CrewAI I don’t quite get/buy the split between tasks and agents. In most examples tasks and agents are 1-1, can’t see any added value by separating some part (frame) in Agent and specific instructions in Task. At the beginning I saw the value in agent having it’s own long term memory but assumed that there land previous interactions, but not - only something called suggestion. So what the story is about? What is the value?