that you may walk worthy of the Lord, fully pleasing Him, being fruitful in every good work and increasing in the knowledge of God;"
Colossians 1:9-10 (NKJV)
Quality and quantity are not the same thing. For example, you could have one diamond, and it would be more valuable than a pile of ordinary rocks. The quality of the diamond is greater that than of the rocks, even though the quantity of the rocks would be greater than the one diamond. But, if you did not understand this concept, you might just think that by having a mountain of ordinary rocks, that meant you were some wealthy individual, but that quantity of rocks does not surpass the quality of the diamond.
Quality and quantity are also something that can relate to what we do as we serve God. The Bible says that we were created for good works (Ephesians 2:10), that God is looking for people who are eager to do good works (Titus 2:14), and that we should be ready to do good works (Titus 3:1). But this does not just refer to a lot of activity, because as Colossians 1:10 tells us, God wants us to be fruitful in our good works. This is talking about quality over quantity.
We may be doing a lot of good things, but are they the things God is directing us to do? This is a big factor in the quality of what we do compared to the quantity. We can do a lot of things, but if God is not leading us to do those things, we may not have much real fruit as a result. We need to be sure that we are faithful to do what God tells us to do, through His Word and by the Holy Spirit, so that we can have a high quality of fruitful good works and not just a quantity of works.