Asking "PrestaShop or Shopify?" usually turns into comparing two feature lists. That is the surest way to stay stuck: both handle catalogues, variants, discounts and multiple languages. The difference lies elsewhere.
These are not two pieces of software, they are two models
Shopify is a service. You pay a subscription, and hosting, updates, security and payment compliance are handled for you. You never touch a server.
PrestaShop is open source software you install with a host of your choosing. Nobody looks after the store for you: not the updates, not the security patches, not the backups.
Everything else follows from that. It is not a question of power, it is a question of responsibility.
Shopify: you rent a machine that runs
Shopify's main benefit is time. A clean store can go live quickly, and the checkout is already optimised, tested at a transaction volume no single site will ever reach. On that specific point, catching up takes considerable work.
The trade-off is the frame you work in. The checkout can only be changed in limited ways, and deeply only on the top tier. Missing features are added through apps, each with its own subscription. And your data lives with a provider: leaving one day is something you prepare for.
PrestaShop: you own the workshop
With PrestaShop no selling rule is imposed on you. Per customer pricing, tiered discounts, B2B terms, approval workflows, a connection to an ERP or a line of business tool: all of it is reachable, because you have the code.
The trade-off is real. A self hosted store that nobody updates becomes a vulnerable store. You need someone, in house or contracted, whose explicit job that is.
Three situations, three answers
You sell to consumers, with a simple catalogue
Clothing, cosmetics, objects, a few hundred references with no complex pricing logic. Shopify. You will be live quickly, the checkout will convert well, and you will spend your time on product and acquisition rather than on plumbing.
You sell to businesses
Price lists per account, quote based orders, credit terms, negotiated discounts, items restricted to certain customers. PrestaShop, or a bespoke build. These rules are your business: forcing them into a frame designed for consumer retail costs more than starting from an open base.
You already run a management system
An ERP, a stock system, a tool that is the authority on prices and availability. The question becomes which of the two connects most cleanly to what you already have. The answer depends on your existing system, not on the platform in isolation. This is the case where a technical opinion before choosing saves a rebuild two years later.
Two assumptions worth dropping
"PrestaShop is free." The licence is. Hosting, updates, modules and the hours spent are not. The cost exists, it simply changes shape.
"Shopify is limited." For the vast majority of consumer stores the limit is never reached. It shows up when your business has rules the platform does not model, which is a different thing from lacking power.
How to decide without regret
In order: write down your actual selling rules, including the ones that feel obvious. Then look at who, on your side, will be looking after the site in eighteen months. Only then choose the platform.
A store is hard to change once launched. An hour spent on those two questions beats a migration.