I think it very much depends on what help, how long for and your own circumstances alongside your own stamina and ability to cope (whether that's financially, mentally or physically).
In my case my parent care days are over as my mum died a couple of years ago (dad died decades ago).
I lived close to my mum, we moved her closer when she got older as the round trip of 2 hours was too much if things went wrong.
She then developed Alzheimer's but lived in her own, small, flat. We started off by getting someone to clean for her out of her attendance allowance as that was what was going wrong. She'd forget to clean the loo, wipe around the kitchen etc., and, with all of us with young children, we'd only manage to do 3 or 4 days between us. The cleaner filled the gaps. All well for a while.
Then she started to forget to take medication (diabetic with a heart condition) so we got a posset box. Then that started to be forgotten or she'd take two days worth at once. She was taking medication four times a day and I was having to go in to supervise and do the 'in between' cleaning. The GP, thankfully, managed to get her medication compacted into twice a day and we bought in someone to cover the evening medication.
She then moved to an extra care sheltered housing scheme and the fun really started. First she was found in reception at 4am, about to step out onto a busy A road. The carers at the scheme managed to get her back to bed. Then she would call at 10pm asking if her district nurse was on the way - she used to come at 10am but people with dementia don't always understand there are 2 of each times in 24 hours. Then we started getting calls at 3am asking when we were coming over (both my siblings and I would pop in after school on a rota).
Finally she started getting mixed up with meal times. She was found by me, her district nurse and the cleaner on separate occasions having her evening meal at 8am (24 hour clock thing again). Then nothing until 8pm as she forgot lunch. Not good as a diabetic...
So we got Wiltshire Farm Foods to do a meals on wheels service and the evening carer would make a sandwich for her. We'd cover breakfast between us and the cleaner was an absolute godsend helping if we were having a break or one of the kids was sick.
Finally she had a collapse went into hospital and they managed to get her a respite place. The respite people assessed her and told social service she shouldn't go home - even with a full care package and us in every day between us she was still too vulnerable.
After 3 months in respite we were given the go ahead for a care home place. The transformation was amazing. For a while (maybe a year) we got our mum back to some extent. She was well cared for and had company every day as she would be taken into the main hall area for the day, every day. We had a place at the local day centre but she started to refuse to go to that when she was at home. In the care home she had no choice and accepted it as part of her routine every day.
The difference it made to our relationship was sad in a way, but very good. We finally had the chance to sit and have a chat and a cup of tea with our mum instead of running around in limited time making sure she was fed, clean and safe. Doing her washing, shopping, ironing, breakfast, organising pills, doctors appointments, cleaning etc didn't leave 'her' time. And the elderly need 'time' with their families.
We were so grateful that she got a place in a good home. The stress of juggling mum, young DS (at the time), and work literally had me sobbing one Christmas. Even with DH helping as much as he could I just couldn't see how I could cope for yet another year.
Don't underestimate what may need to be done and don't feel guilty if, like us, it finally gets too much. Use whoever and whatever you can to get help if you need it. I have a lovely friend who is the kindest person you'd ever meet. She moved her mum in with her. Within a couple of months she could no longer go out with friends as her mum would ring every 10 -15 minutes if she wasn't home by 6pm every night even if she knew where she was. She had to lock her front door every day as her mum managed to wander into the road when she was in the shower one day. When her mum finally died she said to me that she felt old before her time as she was exhausted.