To express a brand you need a set of brand assets. Think of them as a set of tools you can use to build all of your designs and communication: digital, physical, 2D/3D.
Your logo is an important and valuable asset but it is only part of the array of tools you will need to express your brand.
Other assets might be: colour, typography, iconography, form and image style. Tone of voice and materialisation.
The best logos capture the very essence of your brand.
You know you want one.