Is it bad to delete giveaways?

there's no bad consequences ... EXCEPT:

deleted giveaways will count towards the maximum of giveaways you can have open at any time.

that means: if you have deleted 3 giveaways, and your maximum for open giveaways is also 3, then you can no longer create giveaways, until you contact support and they raise your limit.

I think the number of giveawys you can have open is calculated this way:
3 + (number of your successfuly finished giveaways / 3)

doesn't look so bad I think, I deleted twice,

If all you have is deleted giveaways for AAA games, it's a frowny face on your record. But if it's just an average game for a "normal" reason, you're fine.

Even if it's after people have entered?

Man, that's bad. SG admins personally cut one of your fingers off for every deleted giveaway. And when you are out of fingers - ... GabeN will come for you...

If there's a reason why you have to delete a giveaway, it should be acceptable. Just remember that too many deleted giveaways on your record affect the amount of giveaways you are allowed to create in the future and it can also make it look like you create fake giveaways intentionally.

Trip over your own shoes once, shame on you.

Trip over your own shoes twice.....

I would have to say that would be embarrassing.

its not bad. it will just have a record on your profile.

Anyone can have a problem and need to cancel a giveaway. However, too many deleted giveaways on your profile can look suspicious. Personally, I'd only use it if for some reason I wouldn't be able to honor the giveaway I've created. A deleted giveaway is still better than an undelivered one.

If you delete a giveaway that have 0 or very few entries I think that its less embarassing than delete a giveaway with a lot of entries. Accidents happen, and I agree of what Zomby2D said.

one question. i was never in that situation, but i wonder if you can delete a giveaway only before it finishes or it is possible even after, when it is already closed but undelivered. thanks.

If you have a good reason to delete it, I don't think there's anything wrong with it.

YES, except when it's less then 3 minutes and then you delete it