Okay, seriously...
What is a Serger?
Do I need one?
I rarely sew garments. Can it do what my machine cannot?
Why is a serger so "great"?
I have really never knew about them.
Thanks
Kirsten

Grab a t-shirt, turn it inside out, and look at the seams. They will most likely be cocooned or wrapped in thread. That is what a serger does. Here are a couple of articles with descriptions, pictures, and the different options/stitches some sergers can do.

https://www.thesprucecrafts.com/unde...achine-2978199
https://www.mygoldenthimble.com/what...-need-to-know/

I'm like you, I rarely sew garments. I have a serger but I don't use it very often. Maybe once every 4-5 years.

They aren't all that great. They basically just do one thing... overedge a seam. If you aren't planning to make garments, I don't see any reason to get a serger. Some people use them in quilting, but I don't see why, for two reasons. 1) The serged seam is a weaker seam if not accompanied by a regular line of stitching, and 2) there is no reason to finish the edges of quilt pieces, as they will be totally encased and then quilted over.

I have had a serger for about 30 years because I used to sew all my children's clothes when they were small. I mostly just quilt now, and only use the serger when I am making dresses or blouses for my grandkids or for charity.

I have a serger and love it. I don't use it every day but then I don't quilt/sew every day. How I use my serger:
Serge the raw edges of yardage that I wash before using. Keeps the edges from raveling all over the place
Used it to make masks - quicker and easier than stitching
serge the edges of a completed quilt before binding. Makes a nice clean edge to put the binding on
serge the edges of fleece and/or flannel
when hemming a too long dress or pants, serge the excess off the hem and have a clean edge to stitch for the hem. (My machine does not do a coverstitch like the hem of a t-shirt)
use when making pillowcases for charity......way faster than machine stitching
For home dec projects - curtains, cushions and cushion covers
making pet beds
Those are the ones that pop into my head right now but I love having that "tool" available
Sergers have come a long way over the years and they are easier to use - thread- than ever before. Do a google search and read up on sergers and see all that can be done with them. And if you are still interested, a used one can generally be found for a really good price.

I made a lot of knit tops (shirts) with my serger when it was more popular to do. Now I mainly use my serger when hemming pants which makes the job so much easier. A serger cuts the fabric and then stitches the seam. So when I hem pants, I mark the seam...decide how much I need to leave on to make the turned up hem, serge the edge which also cuts off the extra fabric, then I turn up the fabric and complete the hemming process by hand or if it is a pair of jeans or work pants using my regular machine. A serger can stitch fairly fast. I have used mine also on polar fleece. Knits and stretchy materials are easier to seam with a serger as most of them come with a differential that lets you decide how much pucker or ruffle you want in a seam as well as just doing a normal seam. I really don't use my serger much now. But I am keeping it for those certain jobs. I am glad however that the serger I have is a basic four thread model as it will probably last longer than me..

I use my serger for making masks. They work up so much faster!

If I ever took up garment construction again, I'd want a serger.

Otherwise, people say -- you sew right? And I answer, well, no actually I just quilt...

I've never had one and can't say I want one either. I have enough toys lol
I use a zigzag for what you'd use a serger for.

I love my serger and it gets a real work out sometimes. I tired it on a quilt years ago and said nope! not again on a quilt. What it does do great on is receiving blankets and garments. I find there are times, like this time a year ago, where I coordinated and worked with several others to make close to 200 tunics for a Renaissance Festival. The serger was a blessing. The time and finish it provides is great. I for one will always have one. Seems I am always making receiving blankets too.

In 25 years i've had my serger, I've used it maybe twice. I find it to be more trouble than it's worth to setup and thread. Like SusieQOH, I just use the zig zag stitch on my regular machine to finish edges.