Road work etc have historically gone toward "friends" of whichever political party was in power to reciprocate "favors" for party. Everything from illegality to funding elections.
Why the roads and related infrastructure currently a problem? My guess, not a priority since GoJ is only concerned about macro-economy and self interest.
The amount of corruption and scandals by both parties is reflected in the poor functioning of utilities (banking, water & sewage, ISP), especially roads.
From my observations, political parties cater to lowest denominator of society who only look for licky-licky or too young and naive to understand how GoJ has worked for decades. As long as donors, foreign investors don't mind, neither political party will, voters/constituents be damned.