There’s a huge difference between iterators and views. Iterators are use once only, compute on demand, while views are use multiple times, recompute each time, but only the elements needed. For instance:
scala> val list = List(1,2,3).map{x => println(x); x * 2}
1
2
3
list: List[Int] = List(2, 4, 6)
scala> list(2)
res14: Int = 6
scala> list(2)
res15: Int = 6
scala> val view = List(1,2,3).view.map{x => println(x); x * 2}
view: scala.collection.SeqView[Int,Seq[_]] = SeqViewM(...)
scala> view(2)
3
res12: Int = 6
scala> view(2)
3
res13: Int = 6
scala> val iterator = List(1,2,3).iterator.map{x => println(x); x * 2}
iterator: Iterator[Int] = non-empty iterator
scala> iterator.drop(2).next
1
2
3
res16: Int = 6
scala> iterator.drop(2).next
[Iterator.next] (Iterator.scala:29)
(access lastException for the full trace)