I assume the main stuff they are interested in is debt, overdraft and other regular expenses like childcare etc.
Do they care about the amount you spend in shopping or eating out and how much you have left at the end of each month?
After savings a chunk of incone on payday, I leave some disposable amount to use throughout the month (together with other money to pay for bills etc) to spend on family days out and the occasional shopping (notjing fancy but this months I spent £100 on DC for new clothes and shoes and £100 on myself for work clothes for example. Would they see these types of regular spendings like red flags?).
I don’t usually have much left in my main account the day before payday but I do save a chunk of money first thing when salary comes.