Actual death in 2-3 years is unlikely in most cases. It is true, however, that rhododendrons will benefit from having the root ball teased apart when repotting or transplanting from pot to open ground. This can be done using a forceful stream of water from a hose, a pronged cultivator or in the case of extremely tight root balls, a knife. The idea is to expose the ends of the roots so they will grow into the new planting medium.