I use a bearing press, but when I notice a bearing slide into the wheel too easily, it’s usually because the outside of the outer race got coated in excess oil from the manufacturing and packaging process.
When this happens, I pull the bearing out and use a tiny bit of alcohol, degreaser, citrus cleaner, or something similar on a cotton swab to dissolve the oil on the outside, dry the metal, and swipe any residue out of the bearing seat, too.