Percentiles are there as a guide - in height, weight, even in exam results when the poor things get around to that!
Usually (and it depends on the scale and the statistics) the 'average' range is 25-75 percentile, but also someone has to be at 1 and someone has to be at 100, that's what makes averages!! That's the maths!
If you think about it in heights of adults, if you randomly selected 100 adults and lined them up in order from shortest to tallest, there would have to be someone at each end and it doesn't mean that either the person in position 1 or position 100 has anything wrong with their height.