So why exactly is she called a hotel?
Yamato was a very large battleship that was made back during WWII. In fact she was larger than any other Battleship that was made in the war by the IJN. After her inital testing was done, she became reconized by the commanding officers of the Imperial Japanese Navy as pertty much the iconic flagship that represented the IJN as a whole. Because of this, Yamato didn't get involved too heavily during the early part in WWII. She was mostly stationed at Kure, and then later at Truk, and then returned back to Kure at the late part of the war...
Thanks for her highly regarded status symbol and her very high consumption (being the largest battleship made in Japan at the time, she required lots of fuel in order to keep going) she mainly remained stationed and did nothing. Because of this, high rank officers often used the Yamato as place to hold main headquarter operation and dicussions, a lounging quarters and also a luxurious diner. Thus often the high ranks would often reffer to Yamato as "Yamato Hotel" much like the one in Dalian, China.
So yeah, the great battleship that didn't get to see a lot of action was used as a relaxing place for high ranking officer more or less.
This would however change late in WWII when the IJN was drastically loosing ships left and right and also loosing the territory they had control over prior to thier battle with the US. Ultimately they ended up bring Yamato into the battlefeild once when Kure threathen to be under attack by the US. And thus on she was a suicide mission (Operation Ten-Go) to do one thing... stall the US navy and try to drive them back if possible from Kure.
In her battle at Ten-Go she was repeatly bombared by dive bombers and torpedo bombers until she ultimately capsized and went out in a gigantic explosion that was seen for miles. Thus ending the tale of the IJN's most iconic ship from WWII.