Making a Will is not about wealth it is about making sure that what you want to happen to your estate does happen. It gives you the opportunity to specify such things as who will administer your estate, who will care for your children and who will receive specific items of your property.
It is very, very important to be absolutely clear to whom you are referring in your will. Remember that your executors will not have the same knowledge of your affairs as you do.
Even close family members may hold different opinions on the family relationships.
Expressions to avoid include 'my favourite nephew' (without naming him), 'my best friend' (again without naming him), 'the girl who brings round the tea' (an actual example from my experience), 'the man next door'.
It is also highly desirable to avoid nicknames. In one famous case the testator stated 'all to mother' because he called his wife 'mother'. Although this was accepted in court and the wife received everything, the court action could have been avoided entirely by avoiding the nickname.