Most houses are kept too artificially warm for a lot of plants which require a certain amount of humidity in the air. Plants that would have canopy cover in their natural environment normally love steamier environments. But there’s a limit to how many plants you can keep in your bathroom, and misting regularly can be messy and damaging to surfaces and fabrics, so people don’t do it enough to benefit the plant.
In the UK, it’s just not warm enough or sunny enough to keep cactuses and succulents in a regular house or flat that doesn’t have a glass roofed conservatory - they etiolate looking for sunlight, and new growth is weakened.
People think that brown crispy edges on leaves means under watering, but in some plants it means overwatering, so they exacerbate the problem by continuing to water.
A lot of people don’t water plants from the bottom, but just pour on water from the top. Bad on two counts - the water never reaches the roots where it’s needed, and the top of the soil then feels wet, meaning people don’t water for longer, and then the roots die.
Too big a pot - most plants prefer to be slightly pot bound than in a too big a pot - the bigger the pot the more volume of soil it holds, and the greater the volume of water, meaning it’s easy to leave a plant sitting in soil that takes ages to dry out. It’s better to use plant food ( during the active growing period of the plant) and a smaller pot than a large pot and more soil.
Disclaimer : I’m a florist, and spend my working life listening to peoples tales of woe when it comes to house plants!