At work, I try to be very specific in my voicemails. "I'm calling about "specific problem", please call me back at ....". I also am careful about the speed at which I leave my phone number, because I hate people who rattle off their number so fast, I have to rewind the voicemail 4 or 5 times to be able to get the number.
Also, if I return a call and get person's voicemail, then I do suggest that "If we are going to play phone-tag, please tell me what you need to know so that I can leave you a message about your concern". And sometimes we never connect over the phone, but their question gets answered.