First and foremost the garden has to work for you, the owner. Everyone has a slightly different picture of their ideal outdoor space. For some it is a space to sit and dream; for others it is a place to entertain the children or it may be a productive space from where you can enjoy the literal fruits of your labour in the kitchen.
For me personally, it is about colour, light and movement changing across the seasons so that there is always something new to see, as well as something yummy to eat! This may sound like a lot of work and there is no doubt that for me, an hour spent in the garden is a happy use of my time, but that is not the case for everyone.
So the focus will always be what you the owner want for your own garden in terms of its use, its feel and the input it requires from you going forward.
Whilst being sensitive to an existing garden I am more than happy to make substantial changes to a garden where it no longer suits you. I always try and come up with the most environmentally friendly solution possible, to me this means avoiding imported plants (too many plant miles), avoiding plants that need excessive watering or feeding (too much of a drain on resources) and making sure we have as many bee and pollinator friendly species as possible. I tend to use a lot of shrubs and perennials to give the garden structure throughout the year, with the added burst of some annual flowers where needed. I believe this will result in a cost effective and time efficient garden that you can enjoy rather than constantly having to work in.
The garden design should always suit the wishes of the owner, rather than the designer, so whatever you dream of when you think of your garden, be it contemporary, traditional or simply very low maintenance there is a design solution that will work for you.