Of course they don’t and neither should you.
Whether you’re hiring or not, you need to keep up a consistent interviewing practice because:
The experience improves your interviewing skills and keeps them sharp.
You’ll build a list of pre-screened candidates you can call when something does open up.
You may find someone too good to pass up (and, if you do, don’t let ‘em get away).
In fact, the best time to interview is when you don’t need anyone because you’re under no pressure to lower your hiring standards just to get a body on board.