Another possible solution is to give callers who don’t want to leave voicemails other ways to reach you, such as by emailing, texting or visiting your website. “Solve the caller’s problem in the voicemail greeting,” Baldwin suggests. If your outgoing message is informative enough, he says, callers won’t even need to leave a message.
That's why I would definitely resist any temptation to leave any kind of joke message, even if it seems very clever, suitable or relatively benign. People might love it the first time they hear it. The eighth time is definitely going to annoy them. Fa5t3r December 4, 2013

Solution: Make it easier for callers to reach a real person. For example, if you have multiple phone lines, Spectrum Business Voice offers you the option of setting up an auto-attendant that answers your business phone and provides callers with a menu of options—such as particular employees or departments. This way, callers are more likely to reach the people who can help them. A hunt group is another voicemail feature: If one employee does not answer their phone, it redirects calls to another phone line in your business and can keep trying all the lines you have. It will only direct calls to voicemail if no one answers their line.
A voicemail greeting can be pivotal in attracting a potential customer to your company or repelling him! So, it may be worthwhile to utilize some tried and tested tips to frame voicemail greetings for your company. The first line must include a brief description of your company and the services it offers clearly. Tell the callers the time frame within which they will get a call from your end. Ensure the voice used in recording the greeting is cheerful and not drab one. Ensure the greeting is recorded not in a hurried manner so that the callers can understand each word without issues. Try keeping the voicemail message length to 20 seconds or so.