I have a lot of yarns. A lot of pretty sock yarns too. I am a slow, sporadic knitter (I spend more time reading about it then doing it … KH and ravelry). Almost all of my yarns have a project they were bought for, but it will take me years to get through them all.
I am wondering, when do you decide to destash? I was thinking of destashing the yarns that will probably be easy to get again, when I am ready to cast on, and keeping the sweater quantities and my most treasured sock yarns. It’s SO hard to let go. I think the reason it is hard for me is that I don’t work anymore, so it’s just DHs income, and I am worried there will be a day when I can’t afford to re-buy all the pretty, lovely yarns I have now. What’s a knitter to do?:think:
The first thing that comes to mind is – do you still have the space to store the yarn?
If yes – do you really need to destash? You may be a sporadic knitter, but there isn’t any reason to destash if you might use the yarn for some other project.
If no – then you could destash and sell the yarns you decide not to keep for “some day”. You could save the proceeds for other yarn if you are concerned about the budget.
HMM - that’s a tough one. I would say if you have space to store the yarn then hang on to it for a little while. There really isn’t any money to be made destashing so if you don’t think the budget will allow for yarn purchases in the future and you love what you have now…
The only time I destashed was when I had bought a bunch of new yarn when my LYS went out of business and then my mother (an enabler) helped me pick out a bunch of new yarn while I was home visiting.
ya know, you could also invest in those space saver bags, it’d suck all the air out and keep your yarn safe PLUS it’d take up less space 
Most of my stash is about 30 years old and I still knit from it, though I have been buying yarn for the first time in about 30 years and enjoying working with all the new yarns and patterns.
So I don’t see the need to destash unless it’s a space problem or you no longer care for the colors or type of yarn.
space isn’t a problem. I guess I just sort of feel a twinge of guilt at all the yarn sitting and waiting! :lol:
Maybe i should just knit more 
You never know when the knitting bug will infect you. After all the years I’ve been knitting this has been far and away my most productive. I have more FO than I accomplished and almost 20 years. Suddenly I can’t watch TV without knitting, I knit while I am on the computer, I knit while I have my coffee in the morning. My book reading has dropped dramatically, and I now take knitting while waiting for appointments rather than a book.
i decided i had a few i could part with. Some stuff I know I probably won’t want to knit, and some I do want to knit, but know I won’t get to it within a year (or more) and they can be replaced
you can always sell it on the buy/swap/sell board too