"We designed the default voicemail greetings to all users to standardize the feature across all Microsoft services." through. First, having a standard voicemail greeting cannot possibly work for someone who uses Skype for business. Or whose computer is set up to work in one language but expects callers using a different language.
Generally, people that call and leave messages are more likely to be ideal customers of your business. Your voicemail message is often not much more than a formality to the person calling.

Typically, most of these services are uniform—i.e. include the same tools and features (send a script, they record it in a tone you approve, they send it as a file, you supply any feedback, etc.); however, there are some services that go above and beyond. For example, VoiceOverPro, is a single voice professional who records 30 second voicemail messages based on users’ scripts. This is standard; however, users also have options like adding music, recording up to 60 seconds (or 150 words), rush, 2-day turnaround, and even same day delivery.
4. Vacation Day Voicemail Greeting. If your business is off for a holiday, it's a common courtesy to update your voicemail to acknowledge the closure. Mention the closure in the beginning of the message, convey when your business is reopening, and don't forget to wish the callers a happy holiday if the occasion calls for it.