Hola
We stayed last year in May in Tulum. Great place to visit the ruins of Tulum, as well as many other things around (great cenote, Akumal, Coba, the Tulum pueblo itself, ...).
But we hated the hotel where we stayed, Yoga Shala Tulum. Service was not friendly, even when complained of the hot weather - no AC in the rooms and it's not located beachfront. It was easily 100+ in the room. And you had to sleep under the canopy bed because of the bugs, which made it worse. No pool. It's an eco hotel, which is something we normaly appreciate, but there are limits to a zero comfort place (it doesn't have to be hell!).
This was part of a 20 days Yucatan trip that brought us from one side of Yucatan to the other. We never give bad ratings to hotels (as you have to be fair : sometimes you realize you chose an hotel that is not for you, mistakes of that kind can happen), but this is the first time we tell people to avoid at all costs.
Last point on Tulum beach itself: from what I now know and hear on forums, Tulum beach itself is expensive and fairly snobby. It doesn't feel like Mexico at all! We were glad to leave this area after two days, but the hotel mediocre quality surely had a lot to do with this. We much more enjoyed the rest of our Yucatan trip.
Hope it helped,
Joël