When producing a voice over recording (or voiceover, google or narration. nobody seems to understand for sure), the end product is normally nothing however the voice. all by itself. with absolutely nothing else to conceal flaws. Yes, often voice overs are accompanied by background music, such as when narrating short videos, or in podcast intros and "outros." But for the many part a voice over recording is simply that, the voice.
You may desire to specialize. For CITY folks, you can find an animation class or a promos class. COUNTRY folk will need to do a bit of self-teaching here. Check out Terri Apple's Earning money in voice overs.
Among the most unsafe mindsets you can embrace if you're a business owner or a voice-over artist like me is to think you can stop marketing and actively using your efforts to your company, even if you're so hectic.