Welcome to the world of Lexus.
I presume you have a manual gearbox. 1st & 2nd on the manual are renowned for not being what they could be.
As for 3rd, I had some notchiness on the change between it & 2nd. My dealer fitted a modified selector fork under warranty and it's now better that it was, but not, again, as good as it could be when compared to other cars.
The service manager and adviser at the dealer I use both admit that Lexus are "not very good" at manual gearboxes. I can't understand why when they are an offshoot of Toyota - the Avensis box is far better and, in comparison, a joy to use.
Cheers thats the impression im getting why make such a great car and put in a ratchety box.I would have thought by now they would have cracked it