Accuracy in official documents and records proving confusing.

Has anyone else noticed there are quite a few mis-spellings, incorrect dates, names and place names, among the main available records? When following a particular member of the family I noticed that the age of the person was very variable throughout their lifetime! One can understand that in the Census for instance a person’s age can vary every 10 years by a year, due to the time of year the census was taken either before or after that person’s
birthday. But to be out by 5 years and one of my Great Great Aunties (Martha Isobella Chadfield) was down on the 1901 Census as ‘Martha Isabelds ‘. It would appear that we should be cautious when searching through any record where there maybe flaws due to human error. We should therefore, not be too eager to dismiss people due to these errors, where the circumstances surrounding the data prove undeniably correct.