It depends

as some lenses are not at their best wide open and need to be stopped down a bit. That's the theory but I'm happy with all my MFT lenses from wide open. I tend to use them from wide open to f4 and occasionally stop down to f5/f5.6 and very rarely go any further.
I might have said this before but I'm stick in 35mm film land and I still convert everything to "FF" so f8 in FF or f4 for MFT for general stuff with wider aperture for lower light and creative uses is pretty much the norm for me with only occasional stopping down past f4 or f5.6 if it's a zoom wide open at the long end.
Here's two pictures from yesterday taken with a 14mm f2.5, The first at f2.5 and the second at f4.
Here you may be able to see that the war graves in the background in the first are a little soft but in the second the picture is sharp enough all over.
100% crop from that f4 one.
Here we can see that even when focusing on something quite close, Mrs WW, the DoF is massive even at 100% and even at only f4.
One last thing. These picture were saved as 1,000 pixel on the long side at quality 8 and I think they look softer here than the originals do at quality 12 on my screen.