We treat speed as part of the design, and we tell you when you need less than a full store.
Every store starts clean. Then it needs reviews, so you add an app. Then bundles, a size chart, a popup and an upsell. Each app adds its own code, and some of it loads on every page. No single app ruins anything. Fifteen of them can make a store drag on a phone.
Shopify's own help center lists installed apps among the biggest factors in store speed. So a good rebuild usually starts with subtraction. We check what each app earns, rebuild the useful parts inside the theme and clear out what old apps left behind.
Checkout is the other half of the story. Unless you are on Shopify Plus, apps cannot add anything to the information, shipping and payment steps. That means product and cart pages win or lose the sale, so they need to carry the answers buyers want.