Smudging that starts in your fifties is usually not a formula going bad. It is a change in the mechanics around the eye, and understanding which mechanic applies to you decides whether a different mascara will fix it.
The lid position changes. As the skin above the eye relaxes and the lower lid loses a little tone, the upper lashes sit closer to the lower lid and the lower lid sits closer to the lashes. Lashes that used to clear the skin now touch it, and anything that touches transfers. This is the most common cause and it is why people describe the smudge appearing in the same place every day.
The tear film changes. Tear production often decreases with age while the eye compensates with reflex watering, so the lower lid area can be intermittently wet in a way it was not before. A wax formula softens against moisture.
Oil distribution changes. Where skin produces oil shifts with age, and oil is a solvent for the waxes that hold conventional mascara together.
The standard answer to all of this is waterproof mascara, and it works — at a cost paid every night at the sink in solvent and friction on the thinnest skin on your face. Tubing is the better answer, because a polymer sleeve has nothing to soften: it is not held together by wax, so moisture and oil do not break it down, and it comes off with warm water.
The free fix, which no product addresses, is to stop putting mascara on your lower lashes. The lower lashes are what touch the lower lid, and a full coat there is the single most common self-inflicted cause — the diagnostic walkthrough is in why mascara smudges under mature eyes.
