The campaign budget dictates how much marketing spend the campaign could consume. Consider fixing a daily budget of $500 per country ($50 on iOS for CPM billed campaigns) and a minimum of $2,000 campaign budget. The best practice is to set the campaign budget to be, on average, at least five to seven times the amount of the daily cap to make sure that the campaign budget does not limit daily spend and that there is always enough budget left.
Campaigns with a lower budget and daily cap per country might not get any exposure due to budget restrictions. Having a low daily cap can also result in overspending during the first few days, as the system might not be able to predict the performance of your campaign accurately.
The traffic is highly dependent on competition, and we cannot estimate the scale. However, if the daily cap is low, the campaign will experience issues with scale or potential problems with overspending.