I’ve ask the tomato why is she red & she didn’t answer so I’ve decided to check that on GOOGLE and here’s what I’ve found

Tomatoes are triggered to turn red by a chemical called ethylene.

Ethylene is odorless, tasteless and invisible to the naked eye. When the tomato reaches the proper green mature stage, it starts to produce ethylene.

The ethylene then interacts with the tomato fruit to start the ripening process.

Consistent winds can carry the ethylene gas away from the fruit and slow the ripening process. that’s why the tomato not always so red.

not all tomatoes are red. There are yellow, green, orange, mauve, pink and even almost black tomatoes. There are tomatoes with stripped pattern too!

On the contrary, market forces have rejected various color types and red has become the color of consumer choice.