The Mars Rover was intentionally built as low-tech and simple as possible to increase reliability and longevity.
Wikipedia describes “KISS” as an acronym for ‘keep it simple, stupid’, is a design principle noted by the U.S. Navy in 1960. The KISS principle states that most systems work best if they are kept simple rather than made complicated; therefore, simplicity should be a key goal in design, and unnecessary complexity should be avoided.
Some brands are needlessly complicated. “Sophisticated” engineering with complex plumbing/mechanical/electronic systems are more likely to fail, and will cost more to repair. The fewer moving parts and the simpler the mechanics and circuitry, the less there is to go wrong. That’s not my personal opinion, it’s simply math.
So, beware of choosing a hot tub that’s got way more going on than normal. Lean away from models that are needlessly complex, loaded with all kinds of features, because choosing something super-sophisticated can end up being just as problematic as choosing something cheap.