What are the disadvantages of converting a color image to black-and-white by converting it from RGB to Grayscale mode?

What will be an ideal response?

If you convert RGB to Grayscale mode, Photoshop discards all color data from the file, reducing the file from three color channels to a single grayscale channel. This is an effective method, but it is a bit of overkill for the simple task of creating a black-and-white image. For one thing, you've completely lost all color data for the file, so any other components you create, like type, will by definition be limited to shades of gray. Also, as with dragging the Saturation slider to 0, converting to grayscale produces a take-it-or-leave-it result; you can't control how the resulting image appears.