Here's the thing nobody mentions in liner tutorials: the model's eyes are almost certainly retouched, and even before that, she was selected partly because her features photograph symmetrically. Your face — like every human face — is asymmetrical. One eye sits slightly higher, one lid has more crease depth, one inner corner is a touch more open. This is not a flaw. This is just anatomy.
Work With What You've Got
The goal, then, isn't identical liner on both eyes. It's liner that makes both eyes look good — which is a different brief entirely.
Start by studying your eyes in natural light, without makeup, before you reach for a product. Notice which eye is smaller or more hooded. Notice where the lids differ. That five-second audit changes everything, because you stop copying one side onto the other and start making considered choices per eye.
On a more hooded lid, a thick wing drags the eye down and disappears into the fold the moment you open your eye. Instead, keep the line thinner, and angle the flick slightly more upward than you think necessary — it reads normal once the hood closes over it. On the less-hooded eye, you have more room to be generous. The two wings may look different lying flat on your vanity mirror; they'll look balanced on your face, where depth and shadow do the work.
Tool tip: a pencil or felt-tip liner with a fine tip gives you the most control for this kind of adjusted, eye-by-eye approach. Liquid with a brush is beautiful but unforgiving when you're making deliberate asymmetric corrections.
When precision is the enemy of symmetry, removing precision is the fix.
Finally: the smudged or tightlined look is genuinely more forgiving than a precise graphic line, because it blurs the edge you're trying to mirror. A cotton bud dragged along the upper lash line right after application softens any inconsistency almost instantly — and somehow makes the whole thing look more intentional, not less.