It is not completely necessary to requeen your hive every year. The general consensus is that a newly requeened colony will be more productive and have less of a tendency to swarm.
I personally would look for a few indicators as to whether or not to oust the queen.
1) How well did she produce last year?
2) How do you like the genetics and temperment of the colony?
3) Are you prepared for other forms of swarm prevention?
4) How fast is she building up the colony strength this spring? Did she get chilled this winter, or did the cluster keep her warm enough to maintain the integrity of her eggs?
5) Are her traits something that you would want to pass on to her daughters, by making splits, or by rearing queens from her genetics?
If she is a failing queen, but you like the genetics, use her to pass on those traits to her queen daughters.
If the answer to any of the other questions was to the negative, I would consider bringing in a new queen.