With farming, if you want to grow a large crop, you can start small and work your way up. If you begin with a handful of seeds, you have a choice: do you eat the seeds now, or plant them in the ground? If you eat them, your crop is gone… game over. If you plant them into the ground ground, each seed has the potential to grow into a new plant and produce even more seeds. You are then faced with the same question: do I eat the seeds or plant them? A farmer who is diligent enough to plant those seeds year, after year, after year can go from a handful of seeds to a large field of produce. To succeed, you need two things: 1. a disciplined commitment to planting seeds rather than eating them all, and 2. time for your crops to grow.
Something similar is true when it comes to investing. With discipline, we can invest some of our money diligently over time. Doing this allows us to put money to work for us and grow over time. The problem is, we are often tempted to eat all of our seeds (our income) rather than sow it back into the ground (investing for the future).