Why are excessive movement joints undesirable in bridges?

Movement joints are normally added to bridge structures to accommodate movements due to dimensional changes arising from temperature variation, shrinkage, creep and effect of prestress. However, the provision of excessive movement joints should be avoided in design because movement joints always encounter problems giving rise to trouble in normal operation and this increases the cost of maintenance.

Some designers may prefer to add more movement joints to guard against possible occurrence of differential settlements. However, the effect of continuity is disabled by this excessive introduction of movement joints. In essence, the structural reserve provided by a continuous bridge is destroyed by the multiple-span statically determinate structure resulting from the addition of excessive joints.

This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.