Think about for example a planning component for hospital beds... There are a lot of parts that are really straightforward to implement, but for these planning components it might make more sense to develop an in-house component. (Assuming existing constraint solvers and/or rule engines are not a viable solution for you in this particular scenario.)
If your business is talking about updating/deleting/inserting data, you are not describing the actual reasoning behind the change. For DDD, it makes sense to figure out why exactly you are doing the things you do, and model these explicitly in your systems for those parts that matter.
The stereo-typical example for this is an address change: if you model this as an "AddressUpdated", you might as well use CRUD, as this does not specify the intent of the change.
You could change an address because it contained a typo, but you can also change it because someone moved. These might lead to different outcomes, so in DDD you would typically model these as "AddressTypoCorrected" and "ContactMoved".
There are other fine-grained aspects, for example the need of an identity for an object: physical money is considered a value object (so it has no specific ID per instance) in almost all contexts, unless you are the national bank: all of a sudden the identity (serial number of the bill) does matter, so the same "thing" might have different "models" within different parts of the business.
Other examples might be value objects for specific areas, for example weight. Typically weight starts out as a number, and all of a sudden there might be a need to add a precision, mark it as an estimate, or have it "unknown". In order to avoid if-statements all over the code, you construct a "weight value object" that properly manages all of these peculiarities in a single place (i.e. what's the result of an estimate+undefined etc.)