If everything in your mix is stereo, nothing will sound wide. One or two super-stereo parts (eg, clap, mid bass, rides or shaker loop) playing against centred parts will stand out, compared to a blurry, confused mix in which everything is widened. As a general rule, the most important mix elements (kick, snare, main hi-hat, bass) need the strongest mono presence, and the least important stuff (FX, etc) can have the weakest mono presence.
An uber-wide sound will often ‘pop’ out of the speakers, so to highlight one important mix element, try enhancing its stereo content. However, the wider the sound, the more of it you’ll lose in the mono portion of the mix. The secret? Choose your battles carefully, and find that sweet spot.
Balance uber-wide incidental elements against powerful mono parts for the ultimate mix contrast