The first time I stayed at the (then) Hyatt on Collins was a few weeks after it opened its doors in 1986. It was top class then, with bar service at the pool and a splendid restaurant (Max's) on the premises. Many stays have followed since then and whilst the standard of the rooms and of the service have remained about the same, the dining standards are not what they used to be - incl. louder and noisier. The location is as prime as ever. 4/5
Many times over many years the stays were very satisfactory - mostly 4.5/5. The last time (October 2018), showed some inconsistencies: The wrong time for the wake up call to start with, the breakfast cutlery was directly placed on a dirty table and the breakfast cappuccino order needed to be repeated twice before it was acted upon successfully, a bowl was dirty, the alarm clock in the room was not working, in one elevator the security was not working, and in the room the "do not disturb" system was malfunctioning. Ah unfortunate exception from the rule of excellence. 4.25/5.