I've had several motivations along the way, for living frugally and especially concentrating on being a thrifty shopper. When Ron and I first married, we were very blessed to be able to purchase a nice old fixer-upper home - we joke that it was like the house on "It's a Wonderful Life". That house took quite a bit of my time (and everyone else in my family's too!) and I wanted to stay home and work on it as much as possible. Also, I was 27 and my husband was 28 when we married and it was our desire to have a family and for me to stay home with our children. It was almost 7 years before the Lord blessed us with our first child - but that's another story! Let's just say Motivation #1 was I wanted to stay at home.
My husband brought some credit card debt into our marriage (I'm sure it was a result of treating me so nicely while we dated and presenting me with a beautiful ring when we got engaged. So, I take as much of the responsibility as he had, for the debt!) Right away we decided (after listening to Larry Burkett) that we would get out of debt and not go back into it again. My husband took a second (part-time) job and I started working part-time a few days a week. It took us about 6 months to a year to pay off that credit card. From that point we decided it was just too much work digging out of debt and that we would always pay the credit cards off each month or stop using them if we could not pay them off. That was one of the best pieces of advice that we had learned from listening to Larry Burkett and one that has helped us immensely! So Motivation #2 was to pay off our credit card debt and keep it paid off.
These are a few of the reason that we were motivated to live frugally early in our marriage. I have other motivations at this point in my life, and I will post more on them next time.