She was a talented pianist and teacher. All us cousins had lessons and got taught on visits by our gran. She told my parents that if we lived near she could do something with my sister but I had no talent. She said i simply had no coordination or ability.
That's the reason people don't believe they are good at art or music or anything else for that matter.
True story - my music teacher at school told her "clever" kids that I was too thick to learn music at GCSE. I was really, really upset and gave up.
She's probably dead now, and I get offers of paid work both playing and teaching music. So which of us came off better? The only thing in my life I really regret is I believed that teacher and didn't start learning music again until I was 34.
Of course you can learn anything artistic. All it takes is time, and developing the skill of listening or looking depending on what you want to do. I have been playing music for about six hours a day for the last 12 years. I do a couple of hours before my partner wakes up, then noodle in the evening or go out to play with other people. That's how you get to be good at something.
What most people really mean when they say they have "no skill" is that they've tried something and don't have the ability of someone who has spent decades practicing and developed their own techniques and skills. Have a look at Lowry's early work - he certainly didn't start painting "matchstick men" - he could do very realistic portraits. Here's a self portrait from when he was young:
See, it's not that he couldn't do accurate paintings, it's more that he chose to interpret subjects differently as his skills developed.
Yeah, there are some people who have natural "talent" so can learn a subject quickly, but it's not effortless. And people who were talented when they are young often come unstuck when they meet people who have done the work.
If you can't draw or play music or write a novel or whatever, don't blame it on a lack of talent. Skill needs to be developed, and that's down to you. The question is really
are you committed to learn something even though it is hard and you'll spend a long time being crap at it? But saying you have no talent is really an excuse. Get painting, listen to those who are supportive, and ignore people who say you should give it up.