There are at least 2 grades of bike components like cable & spokes. Garbage, and real. I've been riding $200 kiddie MTB for 30 years since they fit my short arms & legs. Cables need frequent adjustment (because they stretch), even at my modest 160 lb spokes stretch & need tightening. And the Pacific Quantum, the plastic crank arms wore out in 3000 miles, and even though I got a replacement bike for $15 at SalvAr resale, I could not get the crank arms off. The diamondback, the pedal threads got wallowed about 3000 miles, and the rear axle broke because of my excessive weight (160 lb). BTW I don't hop curbs or ride over boulders. I ride on pavement.
So I bought a stretch frame unpowered yubabikes bodaboda for $1500 in Jan 18. No shifter adjustments required. Brake cable adjustments not required, just pad pushing when it wears out. 6000 mlles and the crank arms and pedals are fine. I did have to lay the bike on its side and drip oil in one pedal about 4000 miles, it was squeaking. I electrified this bike for $840 with a hub motor, and am very happy with the result. Although I hate PAS, Level 1 too fast and accelerates too fast for the bad pavement I ride on.
Actually I'd love torque sensing, but can't figure out yet how to install it diy on a hubmotor.
I'd suspect at their price point, a trek has cables & spokes made of real steel instead of recycled lead/copper/aluminum scrap metal. A point about bike shops, they get rid of the garbage brands fast because they lose money on warrenty repairs. So figure that in with the shopping. I bought on line, but at my size, the only bikes the local shops stock for me have single speed axles and a Strawberry Shortcake logo on the seat. One is supposed to be tall & leggy to buy a bike in a shop, at least around here. People report when they need a small frame, bike shops make them pay in advance for the bike before they ever sit on it. cities over 10000000 population may be a little better.
Happy shopping.