In an ideal world, voicemail would be unnecessary. There would always be someone available to take customer calls and no one would complain about their calls not being returned and/or rejected. But of course, this perfect world isn’t possible. That’s why it’s important to give your callers options when you are unavailable. For example, aside from leaving a message, callers can also choose to listen to some relevant information about your business (such as a list of your services, your address, directions, hours of operation, and more).
Context does matter here. If the caller would reasonably expect you to answer the phone (such as if they were calling a store or other place of business), an apology for not being able to get to the phone makes the most sense.

Congratulations! You've recorded a professional voicemail greeting that your callers love. If you want them to keep loving it, you'll need to update regularly. Adding seasonal information and varying your message keeps your greetings fresh, which is especially important for businesses whose clients and customers call in on a regular basis.
Want some sample business voicemail messages? Below are 21 pre-recorded business voicemail greeting examples to get you started. You’ll find voicemail examples for your business’s main phone number, your direct business line, your after-hours (or non-business hours) voicemail, some holiday-specific greetings, and your customer service line. Even better, all these voicemail greetings are free and you can download the voicemail’s mp3 file!