Most building entrances are inadequate to stop reception floors getting wet.
A canopy, even a small one, can help to make a difference, as illustrated in this photo:
Here you can see a thin strip of dry paving where the canopy has managed to stop the rain.
The principle of an entrance is to ensure your feet are clean and dry before you step onto the floor inside. If you can ensure that some of the pavement outside is dry, in addition to matting inside, this will help your cause.
How to tell if your entrance works?
Stand inside on a wet day. If you can see liquid on the floor e.g. wet footprints, your entrance system isn’t doing its job.
This is when you should definitely look to improve the wet slip resistance of your reception floor.
Does your building’s entrance system actually work…?!