No, we buy new or nearly new and run them into the ground. Far cheaper to run that way that constantly buying on the never-never. The money we save by not having a monthly lease/loan repayment to pay more than covers the cost of the next car after, typically 10 years or so.
Modern cars don't need much money spent on them if they're well driven and regularly serviced. If you can't afford new or nearly new, then get a low mileage used car with a full service history.
Modern cars last on average 13 years, so changing every 3 years is just wasting money. Of course, it's fine if you want to change for the "glory" attention seeking of regularly having a new car, but you pay for that priviledge!
Both our current cars were bought new, mine is now 14 years old and OH's is 7 years old. Average annual "cost" of purchase depreciation, breakdown cover, repairs, MOT, servicing, etc including tyre repairs/replacements, is around £750 per year. That's typically 3 months leasing (average £250 per month) for people who always want new. So basically, we're getting "free" car use for 9 months of the year compared us replacing every 3 years!
It's a no brainer to buy a decent car (in terms of mileage and service history) and run it till it drops!
And in my 40+ years of driving, I've never had "expensive" repairs such as new gearbox, new clutch, new engine, etc. All I've ever spent on are consumables, such as brakes, tyres, occasional new exhaust part, track rod ends, occasional battery, cam belt after 10 years or so, etc. So, never had the problem of repairs costing way more than the value of the car, etc. I put that down to careful driving, and regular servicing. I.e. if you have the cam belt changed on schedule before it breaks, it's a hell of a lot cheaper than repairing/replacing after it fails!