Cheap works for non-professional projects. I’ve used Behringer, Alesis, and other inexpensive mixers for sound systems. The tradeoff is cheap generally means you might be replacing the board in 5-10 years. The Alesis mixer lasted about 6 years before the pots got noisy. My karaoke system is a mid-range 16-channel board, and it’s going on 15 years trouble free.
If all you need is to set the levels and parameters then leave them alone, cheap will work. If you’re making changes while recording or performing, cheap will eventually fail you.
Electronics are pretty reliable. Cheap mechanical parts are not. High end systems are be able to withstand the rigors of setup and takedown, dusty environments, and frequent transportation. If you keep a cheap mixer indoors and cover the controls with a dropcloth to minimize dust, it should last quite a while.