There are both Palestinians and Israelis living in the West Bank, but they use different roads. Palestinian roads tend to be older, sometimes made unusable by roadblocks; Israeli roads tend to be more modern, constructed by the Israeli government exclusively for use by Israeli settlers. Palestinians are forbidden from using the Israeli roads, unless they are able to obtain a permit, in which case they may be able to use a certain section of a certain road, but in all other cases the roads are segregated. Since the only Israelis living in the West Bank are Jewish, and the Palestinians enclosed in the West Bank are Muslim & Christian, this amounts to one kind of road for Jews and another kind for Christians & Muslims.
Roadblocks inconvenience movement on many Palestinian roads. Palestinians must switch from one car, taxi, or bus and to another waiting on the other side of the block. This increases the price of travel, especially for those who could otherwise use their own cars. This hindrance of movement has a damaging effect on the economy, and is a serious health hazard as it prevents sick people from being transported quickly to hospitals, when necessary.