Why are stand alone computers harder to hack than computers connected in a network?

1) A stand alone machine is less likely to be known...

2) A stand alone machine doesn't have much to offer

3) Most stand alone machines are switched off when not in use

4) In a network, it only takes one weak computer to bring the whole thing down.

5) A network usually has some form of remote access enabled

6) Alot of hacking starts from inside the network.... most hackers learn to hack on work/school networks that they already have some form of legit access to.

7)Alot of stand alone machines get hacked but nobody notices unless the hacker does something massive to grab attention, whereas on a network there is usually an IT guy who will know the network is being probed before the attack even takes place.

8) Nobody cares if a standalone gets hacked, if a big network gets hacked its everybody is gonna know about it

9) Im sure there is alot more reasons but i cant think of any more just off hand.