This guideline covers a few different situations.
First, it’s good manners in any culture to use your initiative to correct things that are not right. For example, are the dishes piling up? Wash them. Is a log blocking somebody’s driveway? Move it. It’s common sense and basic human courtesy. We shouldn’t need to be asked to do things like this.
For Samoans, though, verbally offering a service – as good as your intentions might be – can be considered insincere and disrespectful.
It’s in the Samoan nature to (at least initially) decline any gifts or kindness, so if you ask someone something like, “Would you like me to wash your car?” it’s like you’re expecting (hoping?) that the person will say, “No thank you.”
So why would you bother to ask?
If you really wanted to wash somebody’s car, you’d just wash it.
If you really wanted to feed your visiting Aunt, you’d just bring the food to the table.
If you really wanted to help your host clear up after dinner, you’d just do it like Nike.
Yes, this rule of Samoan etiquette can get a little tricky sometimes. What if you serve ice cream to a guest who’s lactose intolerant, right? Or, helping to clean someone’s kitchen might require you to go into their drawers and cupboards, and not everybody’s comfortable with that, especially if you gave no prior warning.
In these situations, you just have not take it personally if your gesture of kindness is rejected. At least you’d come out of that instance respected for trying (and not just talking about it).
What’s your experience with this Samoan way of doing things?