This is relevant because different areas of the house will be used for different purposes and are therefore subject to different types of traffic. For example, entry areas such as inside the front door will be subject to people in their street shoes, work boots, etc. This type of area must be able to cope with (a) a lot of footsteps, (b) hard footwear and (c) lots of dirt.
On the other hand, areas such as ensuite bathrooms will probably be limited to people with clean, soft footwear or bare feet.
You can get different types of tile to suit different situations. For example, you may be able to purchase more decorative but less durable tiles for your bathroom. This is more cost-effective than purchasing heavy-duty tiles designed for high-traffic areas.
So... your first task is to write down the area(s) the tiles will be installed, and a list of the amount and types of traffic the area(s) will need to handle.
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