Why Do 90% of Consumers Struggle with Sizing?

Sizing should be simple—small, medium, large. But for most shoppers, it’s a guessing game that often ends in frustration, returns, or regret.

90% of consumers struggle with sizing due to inconsistent standards, lack of fit transparency, vanity sizing, and the challenges of online shopping without physical try-on.

In the fashion world, size confusion isn’t just annoying—it’s costly for both brands and buyers. Let’s explore what’s broken and how to fix it.

Why is sizing so inconsistent?

You buy a size 8 from one brand and it fits. The same size in another brand feels like a 12. What gives?

Sizing is inconsistent because different brands use unique measurement systems, fit models, and grading rules—plus trends and regions influence how sizes are designed.

Why can’t brands agree on standard sizes?

Because fashion isn’t built around a universal sizing system. Every brand creates its own size chart based on:

• Their ideal customer profile¹
• Specific fit models used in development
• Regional sizing norms (US, EU, Asia, etc.)
• Style intent (oversized, tailored, cropped)

I once bought three size 30 jeans from different brands. All fit differently. One was loose, one tight, one perfect. It wasn’t me—it was the label.

What role do factories play?

Factories often use different grading rules², which affect how sizes increase across a range (e.g. XS to XL). A 1-inch increase in the waist may be normal for one brand—but too generous or too narrow for another.

Also, bulk production tolerances³ (e.g., ±0.5 inch) can further impact fit. Without tight QC, two size “M” items from the same batch might feel different.

What is a sizing issue?

Sizing problems go beyond a pair of tight jeans. They impact confidence, brand trust, and return rates.

A sizing issue refers to any mismatch between the expected fit and the actual garment fit, often caused by inconsistent measurements, unclear labeling, or poor product information.

What are common types of sizing issues?

• Label mismatch⁴: Says “L” but fits like an “S”
• Uneven grading: Sizes increase too much or too little between options
• Inconsistent fit⁵: Same size, different fit across styles
• Unclear chart: Size guide shows body measurements, not garment measurements
• Style confusion: Oversized vs. slim-fit not labeled clearly

I once ordered a blazer marked “true to size.” It arrived stiff, boxy, and fit like armor. Turns out the brand had changed factories—and forgot to update the chart.

Why are sizing issues such a big deal?

Because they create returns, wasted production, and lost customer loyalty. In eCommerce, over 60% of returns are due to bad fit. That’s money out the door for brands—and time wasted for consumers.

What is the psychology of vanity sizing?

We all love fitting into a smaller size. And brands know that. That’s why “vanity sizing” exists—but it comes with a cost.

Vanity sizing is the practice of labeling clothing with smaller sizes than the actual measurements to make consumers feel better about the fit, even though the garment hasn't changed.

How does vanity sizing⁶ influence buying behavior?

When shoppers see they “fit” into a smaller size, it:

• Boosts confidence
• Encourages repeat purchases
• Creates emotional attachment to the brand
• Builds the illusion of flattering design

Vanity sizing works—short term. But it’s deceptive long term.

I once had a client who labeled their size M as size S to align with competitors. Customers were thrilled—until they tried a tighter-fitting style and felt betrayed. Returns doubled.

Why is vanity sizing harmful?

• Creates false expectations⁷
• Confuses sizing across brands
• Causes emotional friction⁸ when customers size “up”
• Complicates online shopping and reorders

The better approach? Accurate sizing + clear fit guidance. Customers want clothes that fit, not clothes that lie.

How do I choose my size for online shopping?

Buying clothes online shouldn’t be a gamble—but without trying them on, many shoppers feel like they’re guessing.

To choose the right size online, use garment measurement charts (not body size), read fit descriptions, check return policies, and compare with items you already own.

What steps help you get sizing right online?

1. Use a tape measure – Know your chest, waist, hip, and inseam
2. Compare with your own clothes – Lay a favorite piece flat and measure it
3. Check garment size charts – Look for flat measurements, not just S/M/L
4. Read fit notes – Look for terms like “oversized,” “cropped,” “slim fit”
5. Look at model info – Compare their size and height with yours
6. Check reviews – Other buyers often mention if it runs small or large

When I shop online, I keep a note in my phone with my actual garment measurements. That 30-second reference saves me time, stress, and returns.

What else can brands do to help?

• Use real-world models with size labels¹⁰
• Show video try-ons from different body types
• Offer size recommendation tools¹¹
• Allow free, easy returns

Sizing isn’t one-size-fits-all—and it shouldn’t be treated that way.

Conclusion

Sizing problems aren't just about numbers—they’re about trust, confidence, and the ability to enjoy clothes that truly fit. Until the industry standardizes, the best we can do is shop smart, measure often, and demand more transparency from brands.