One source, different applications
In practice, product knowledge is often scattered across the organisation. Article data is stored in the ERP system, texts and images are managed by marketing, technical documentation is kept by colleagues and specification texts are maintained somewhere else again.
You notice this most when something changes. Suddenly, the same update has to be made in several different places.
A website, product sheet, specification text, configurator or data feed may each require information in a different format, but they all rely largely on the same underlying product and application knowledge. That is precisely why it pays to organise the source properly.
A PIM can help, but it is not the starting point. The most important question is much simpler:
Where is your product knowledge stored, and how much effort does it take to find the right answer?