In my scale of voting a 1 is a terrible photo which doesn't meet the challenge and is offensive in some way. So my 1 votes are rare to non-existent. My 2 votes are pretty rare too and 3s are uncommon. The reason that the bottom end of the scale is hardly used by me is that most people here present photos with at least some merit and therefore don't deserve to be insulted.
I vote unusually high in an effort to boost morale. I know so many people have left because of low voting and I try to
compensate...a loosing battle but...
From the voting guidelines: rate entries on a scale of 1 to 10. A score of 1 is a "bad" photo, and a score of 10 is a "good" photo
Yup, those are the guidelines.
And yet... I almost never give out 3-or-lower to a challenge entry. Why? Because from my point of view pretty much everything entered in our challenges is, at worst, just a somewhat subpar image. I wasn't always like this; I used to operate from what I conceived as a "higher plane" or something silly like that, where I convinced myself that my personal, aesthetic judgment was in some way, sort of, "absolute": if I didn't like it, it wasn't any good! In effect, I was thinking "DPC has WAY too many water-droplet shots (this was a thing back then) and folks that enter them are just being copycats, there's nothing original here, it's my job to discourage water-droplet shots by giving them 3 or even 2, maybe folks will wake up and realize..." blah blah blah internal monologue continues ad nauseam.
Thankfully, I'm over that now. I recognize that personal preferences (mine, yours, whoever's) are personal preferences, and not some sort of license to lash out against whichever entries don't align with them. The best way to express my preferences is to vote them UP, not to vote the others DOWN. Someone has to do a really aggressive job of being sloppy, off-topic, or just plain offensive to get a really low vote from me. I think THAT's what the "full scale" is for.
This is just my personal story, and everyone's entitled to their own :-)
If anyone is to grow as a photographer, they need honest feedback. Giving a truly bad shot a 5 (or higher) is not really helping them grow. I don't give very many 1's, but I will give them if I feel it is warranted. I also don't give very many 10's. I base my scores on how good I think the photo is and how well it meets the challenge.
My personal baseline is 5 and very rarely dips below that. An image has to be pretty shoddy, or very blatantly in-your-face DNMC for me to vote lower. Most entries actually try to meet challenge criteria.
I'm with tuba dad. I use the full scale. Or at least, I try to. Sometimes I skip 1 and 2. It's there, so might as well use it. I'm more interested in my placement, and I find it disappointing to get a high 5 and still end up in the bottom third of a challenge. I find that demotivating, not low votes.