9y
As recruiters, we have seen that many employed candidates prefer to talk on weekends or their day off work to not conflict with their current job. We leave messages and emails and the candidate can coordinate or schedule a time to speak when they are available.
As far as scheduling goes, there is a lot more that goes in to it than meets the eye. We have to coordinate with multiple managers that are extremely busy and also other candidates that we have spoken to and scheduled first. Sometimes there are not a ton of options for interview times especially when we already have multiple candidates booked and the first round of interviews is near the end. Ultimately, we try to be as accommodating as we can with candidates and work around their schedules as much as we can.