Loads of people do. If you read on here regularly every second week there is a post about regretting kids, or wanting a different life. So whilst people might not admit to it in real life plenty do on mumsnet.
For my tuppence worth I don't regret it, I have 3 and whilst it's taken a toll on me physically would do it again in a heartbeat. However I have a supportive dh who is an equal partner, none of this I work full time so can't possibly take care of the baby when I get in or do the dishes over here. I wouldn't have settled for anything less and we discussed this before having kids, if he had been a lazy arse before I wouldn't have stayed with him much less procreate. He understands how important my work is to me and facilitates it by wfh previously and now compressing his hours so he can have baby whilst I'm at work. I have a professional job that pays well, even though I will be working 16 hours it is still more than worth my while to work. I enjoy my job but am happy with the work life balance I have, I wouldn't have wanted this earlier on in my career and purposefully worked full time prior to kids. He does night shifts with ours when they would wake as babies so I could sleep and shares the load.
I knew there would be difficult bits like the sleep deprivation, potential colic etc and appreciated there would be mundane bits so that didn't come as a shock to me. Those no point complaining about hating changing nappies for example, they can't change them themselves, it shouldn't come as a shock and really nobody enjoys it.
You have to adjust your expectations so holidays might be to child friendly places, might take a little planning etc. I think the main issues come from if you don't have a partner who does 50:50 so your plate gets overloaded and you don't adjust your expectations. It isn't all enjoyable or sunshine or rainbows. It can be hard, really take its toll but on the whole I love it.