I started out doing computer recording waaaay back in the day with Cool Edit Pro. It worked great and was easy to use, but was later bought by Adobe and renamed Adobe audition . . . and they initially wanted too much money for it (although I see the price has dropped an awful lot on the product since) so I switched to Audacity. I found Audacity pretty easy to use as well, so started recording with it for a while. The more I used it though, the more I found certain things about it annoying.
I dunno if it was something specific to my setup, but Audacity would occasionally crash. There's nothing more annoying than unreliable software when you're trying to write/record a song. I tend to record a grab bag of stuff - guitar (electric and acoustic), bass, vocals, hand drums, percussion, mandolin, harmonica, etc. Usually just using one or two mics but occasionally three or four at a time. I found multitrack recording was always kind of clunky in Audacity. There are a limited number of tracks that it supports, although for basic rock recordings I never ran into problems with the limit. Waaaay worse than that was adding/previewing effects when mixing. The preview was very slow to operate and made it annoying and difficult to get the perfect settings you want for a particular sound. Audacity doesn't support VST instruments (or at least didn't when I was using it). So if you want to add some cool pads to a song or a little background riff with a cheap MIDI controller you're out of luck. In general, MIDI support in audacity kinda sucks.
So I ended up with Reaper. Reaper is powerful and flexible, but occasionally very annoying. I had to sit down for a few days and go through tutorials to get comfortable doing basic recording stuff. Once it's all set up and running though, it's much nicer to use. It was easy to integrate my midi controller for doing basic things starting/stopping/looping recordings, undoing stuff, etc. It was generally straightforward to use my virtual instrument libraries and get them working with midi. Multitrack recording is easy. It's easy to apply and tweak VST effects. Doing complicated sends/returns to outboard compressors/EQs is pretty easy. It's very solid/stable and I've never really had problems with crashing. Pretty much any setting I want can be quickly made part of my workflow and saved. It's a very efficient environment for working in, and I feel like I'll never need a different DAW. Everything I've tried to do has been possible (although often requires that I look up a tutorial). But there is an up front cost to learning it that was kinda painful at the start. After using the demo version of Reaper for a couple years, I actually felt it was worth shelling out the few bucks to buy it.