Mary McAleese is living proof that you never know how a leader will perform until after they are in post.
This week, Peter Robinson led tributes on her last official engagement in Northern Ireland as President of Ireland.
At the dinner in Hillsborough Castle, Robinson singled out the Queen's recent visit to the Republic as being Mrs McAleese's "crowning" achievement.
Puns aside, few would have predicted this outcome before she took office.
Unionists were appalled; one commentator even called her a "tribal time-bomb" because of her northern nationalist background.
She did make the odd slip; for instance, comparing Protestant sectarianism to Nazism. But she was willing to apologise and, even in a society where we are quick to look for offence, her sincerity was eventually accepted.
Mrs McAleese has been an outstanding president, who has brought about real reconciliation within the island and between Ireland and Britain.
She is someone who had been both forced from her home in Ardoyne by loyalists while still a child and subjected to sustained political abuse when she first stood for president and took office.
Many would have been embittered by such experiences and looked for a way to hit back. The fact that she rose above personal abuse makes her an example for the rest of society - precisely what a head of state should be.