1) If you have had a repayment mortgage for a number of years then whatever equity you have in your house can be used as a larger deposit for your next property. Obviously this may take a while but people shouldn't just depend on increasing house prices in order to move up the property ladder.
2) With the current Bank of England base rate being so low (the sun shining) hopefully you will be paying a better percentage of your mortgage off (there you are in the fields making hay) ....in turn increasing the equity in your home.
Sorry if it was a confusing analogy (not sure if that's the right word), cliche perhaps, but it made sense in my head