This was a small issue at first. The water has to be able to be in the tank long enough for it to heat up. Low flow anything will have water that is not as hot. Sinks have to have a diffuser.
These fail because the magnesium or aluminum Anode rod has been eliminated by doing its job, to attract the sediment and corrosive elements (like minerals in the water) so that they corrode the anode rod rather than the inside of your water heater tank. When it is gone your tank starts rusting. These were about $10 at HD 10 years ago but now about $35. Water heaters don't last long in OK because of the water. Replace that anode.
Ha! Good memory! Yes, had a water leak under our concrete slab on our home that just closed escrow a couple days prior. We were leasing back for two months but it all worked out fine in the end. It happened to be the hotwater line under slab running from the tank in the hallway, under the dining room slab to the kitchen. I happened to be standing barefoot on the engineered bamboo wood floors and noticed a warm spot on the wood floor that was just on the other side of the kitchen counter where the sink is located. THe warm spot on the wood floor was about the size of a basketball hoop. Didn't have any water leaking up through the concrete or wood floors, luckily. Don't know how long it had been going on or how long it would have taken to leak up through the concrete or wood had it been the cold water line or if we would have ever noticed it in the two months remaining in the home.
