Generally speaking Battlefield has two types of objectives. Infantry objectives and vehicle objectives. Infantry objectives are only accessible by infantry, or have a significant amount of cover, meaning that any vehicle entering it would be at a major disadvantage. Vehicle objectives are the exact opposite. They have enough room for vehicles and very little cover.
The most important objectives at the center of the map are usually infantry objectives, while the objectives at the edges of the map are usually vehicle objectives.
The Manhattan Bridge map is a good example of failed map design.
The B objective on conquest (The objective at the top of the building near the bridge) has at least 8 entry points, 2 grappling hooks on each side of the building. Yet the objective itself is fairly small. This leads to a weird situation where it's both a pain to push, but also a pain to defend. You can't push because people can just be shooting down at you and can hear you coming up on the grapple hook. You can't defend because you can't reasonably cover 8 sides at once. So it becomes a chaotic mess.
The A and E objectives are similarly terrible, but that's because you're forced to capture in the middle of the street, while there's a ton of buildings surrounding it. It's neither a vehicles nor an infantry objective. It's too closed for vehicles and too open for infantry.
The C objective is chaotic, but it's mostly fine. With the support of a vehicle and some smoke grenades, you can at least effectively attack it. The D objective is mostly fine as well as long as you make sure you secure the high ground before you start capturing the objective.
