The Roman conquest of Britannia was protracted so when did it really end?

Julius Caesar made two tenitive recon enforce "invasions" of Britannia the first being an utter military failure and the second being only marginally more successful. The Romans contented themselves to "influence" through trade and the "acceptance" if you will of noble's children as hostage Britannia until about 43 AD almost 100 years after Julius Caesar's first two recon visits. Beginning in 43 AD Rome was fed up with the feuding between clans in Britannia that caused trade interupptions, so they decided to invade Britannia and show the Celts how to run a country effectively. (Sound faintly familiar?) They even did it because it seemed like good business and maybe even it might be good for the survivors of the invasion. Rome needed Britannia's zinc and other mineral wealth. Rome acted almost as if they really didn't really want to conquor Britannia as evidence of this almost ambevalent attitude toward the conauest of Britannia The conquest of Britannia took at least five decades and some argue that the last battles for territorial control took place over one hundred years later and that in reality Rome never really controled Scotland or for that matter some parts of Wales.