It occurs to me…
A cell by itself only needs nourishment (food & water) and movement to survive.
Any cell that is in a cooperative environment (tissue, organ, organism) MUST also have a communication mechanism.
This is not about pain, disease, discomfort. It is essential just to survive and live. It is essential to maximize the life of that multi-cell organism.
How many cells do you have? Is your communication mechanism working well without interference?