Most car manufacturers tend to have a car in every class these days. Hence the reason over the last decade we have seen BMW X5's, Audi Q7's etc. Then came the "cross-over" cars, Nissan Qashqai, Kia Sportage etc. So then BMW release the X3 and Audi the Q5. This is the reason Porsche released the Cayenne, Macan and Panamera. Otherwise they would miss out on market share.
Ferrari get around this by using Fiat. This is their "everyday range". On the flip side of this Nissan wanted to tap into the Luxury market and released their "
Infiniti" cars. Toyota do this with Lexus.
One final note. If you think the Porsche Panamera is bad, look at the Aston Martin Cignet: