That's a negative signal as well: it shows that you job-hop frequently, get bored easily, and can't commit to any one company. In some companies (particularly startups) that's fine, in many it's the kiss of death.
I think that what hiring managers want to see is that you fully exploit the opportunities available to you. That means that if you're in a good employer and given a lot of responsibility, you stay. If you're in a dead-end job where you're not learning anything, you leave. If it's a good company going through a rough patch, you stay. If it's just a bad company, you leave.
Oftentimes that means you'll have stints of varying lengths on your resume: you may have a few of 1-2 years when starting out to find your footing, then a longer stint of 4-5 years at an industry-leader, then a shorter stint at a smaller company where you're given more responsibility, then a startup, and so on.
Unless you manages to get on the gravy train, in which case, congrats!