It depends on which "culture".
Sports Culture - For my team, and my kids' teams, if you are on time, you are late. Be there 10 min early and ready to start practicing on the dot. If you are late, you’d better be running to join your team and looking sorry! Don't schlepp on over looking like you don't have a care in the world. It's so rude and disrespectful to your teammates and you coach who is taking the time away from THEIR family and life to coach you.
Work Culture - For my department/work, on time is considered anywhere close to the time you say you will be there. For example, I like to “start” at 7:30am, but as long as I am there or online before 7:50-ish, I don’t bother calling/texting my boss. If I think I will get there later, I will text her that I am on my way so she doesn’t worry. It’s not that I am being disrespectful, it’s that our hours are flexible and project-based and we work until the job is done, not until a certain time on the clock, plus we work from home a good amount of time, so the “start time” is basically a time we set ourselves for when we would like to get in/on and get started, not really a company-mandated time. Some of us like to start early at 7-7:30am and leave/log off by 4, and others like to come in/log on closer to 9am and work later into the evening.
Family/personal culture - For parties, I like being about 10 min later than the “start time”. I hate being the first one there, and hate walking into a crowd in full swing, so I try to plan it to get there at just the right time.
For a dinner, I def will be there on time. If the host says dinner at 6pm, we will be there before 6pm! However, I do often notice that the host does not have dinner ready on time most of the time. Nothing is more annoying than expecting to eat at 6pm and you get there and the dinner hasn’t even been cooked yet. Then you aren’t eating until 8.
Work again - Work meetings, definitely be ON TIME. Like to the minute. Most of my work meetings are conference calls. I call in 2 minutes before the meeting starts. Usually, the meetings start on time.