Sweaters are large and require quite a few rows and stitches. It takes hours and hours to finish. There are some amazing patterns out there (like my Love Sweater) and you should try it out sometime. But these are not good initial projects.
Knitting a size M sweater with standard needles (4 mm) can take 40-50 hours to finish. It can be much more if it is a complicated multicolored pattern, but also less if you use large thick wool and it is only knitted in jersey point. Learning the basics usually doesn't take more than a few hours, but building muscle memory can take a while. After you've practiced enough, you'll learn to knit faster and your weave will become more even.
Eventually, you don't even have to look at your hands while knitting. It should only take a few hours to learn the mechanics of the fabric to assemble it, make basic stitches and finish it off.
To be able to knit
at a good level, you have to spend some time practicing. By the time you've completed 2 simple projects, you should be knitting evenly and showing real progress.On average, it should take you 20 to 30 hours to learn how to knit well. This equates to about 2 weeks if you can knit just a couple of hours a day. I started with this, but it's gone up a lot in price and it's really not worth it (read my Basic Knitting Supplies for Beginners to learn more about it). For example, Stefanie Japel leads a class called Knit Lab, where she explains the basics of knitting, starting with the supplies you'll need.
Everything I mentioned is what makes knitting such a fantastic pastime that it will accompany you throughout your life. It's important to understand that people vary greatly in how long it takes to weave a standard they're happy with. In addition to more detailed designs, advanced knitting projects often contain intricate details such as ribbing, flowers, etc. Most patterns (such as linking) will explain what abbreviations they used (K%3d knit, P%3d purl, sl %3D slip, etc.
There is always something new to learn, always new and exciting projects for get started, and it never gets boring. It's horrible to have to unravel your fabric, but sometimes doing it and realizing what you were doing wrong can improve your skills to no end. Try both and you'll probably find that you prefer knitting for certain types of projects and crocheting for others. Once you are a fresh, calm and competent weaver, if you wish, you can work to increase your knitting speed.
Thank you for pointing out the link between women's rights and the popularity of knitting and other crafts. It also speeds up the knitting process because you can tell by looking at your fabric which row of the graph you made previously or how many decreases you have already made. It is possible to achieve a tight stitch through crochet; however, this may require you to master advanced techniques.