Compatibility with the actual installation
It is not enough for a module to claim support for “PrestaShop 8”. The exact version, PHP environment, theme, overrides and other modules touching the same workflow must be considered. Checkout, carriers, payments and stock are common areas where extensions can conflict.
What it changes in data and core flows
A serious module should be clear about the data it creates and the hooks or services it uses. The more it alters core behaviour through non-standard mechanisms, the greater the cost of future upgrades.
Before production installation, a backup is essential and critical functionality should ideally be tested on staging or a copy of the store.
Performance and scheduled work
Modules that scan large catalogues, synchronise stock, generate exports or call external APIs need controlled execution. A heavy operation triggered on every page load can make an otherwise fast store feel slow with no obvious explanation.
Maintenance is part of the purchase
Initial price is not the only criterion. A module that is maintained, has clear logic and can be technically reviewed is usually cheaper over time than a low-cost extension that blocks the next upgrade.
That is why i-2 ready modules focus on a defined scope and predictable behaviour. When the ready functionality does not fit the process, we prefer a targeted customisation rather than stacking overlapping plugins.