Upvote:2
The consulate needs to know that you have a job to return to after your trip.
If you can't even tell your employer that you're planning a vacation, it is difficult to imagine that they would take it kindly if you suddenly go on one.
And if you're willing to go an a holiday which is likely to cost you a job, then it is very hard to imagine that going on a holiday is your real motivation -- and much easier to think you're probably looking to immigrate illegally.
Once this suspicion has been raised, there are not many good substitutes for a declaration from your employer that you would not lose your job by going on the trip. Something like a binding offer to start a different job after you come home might do.