Any cheap machine is likely to be a throw-away. I've already been told by my sewing machine service guy that the cheaply made Brother embroidery machine I paid $500 for is not repairable if something ever breaks on it. I didn't realize that before I bought it or I never would have bought it. However, since it's only used for embroidery and I don't do much embroidery, I'm hoping it'll last quite a while. My main machine is a Viking, and I also use my Chandler industrial machine quite a bit, which saves a lot of wear and tear on my Viking.
OTOH, I wouldn't make a big investment if you're not sure you're going to want to continue with that hobby. If you buy a cheapo machine, IMO it should be considered a starter machine, and when it dies, then upgrade to something of better quality if you've found you enjoy sewing and would use the machine often.
Annual service on a sewing machine in our area is a minimum of $90 each time, per machine. That's just for cleaning and adjustments. It's higher if there's anything really wrong. Check to make sure before you buy any machine that you will be able to get service for it in your area.
What I would recommend is buying a good used machine from a reputable sewing center. You can often get great discounts on basic machines that people have traded in when they upgrade to that $5,000 fancy machine.
Sewing machines are tools, and like many tools, better machines will help you avoid the frustration of dealing with a poorly made tool that doesn't work as well as it should. Professional tools help you create professional-looking results.
Not all machines are created equal. You have to decide if a cheap machine will serve your purposes as well as a better quality machine, and if you're willing to just throw away the cheap machine when it breaks, or if you prefer something that will be fixable.