I am being sponsored by my company and they have arranged all the documents for me but by mistake I ticked on an extra column on my checklist and later I realized I didn't provide any documents for that. Are they going to reject my visa?
Are they going to reject my visa?
This is an opinion based question however no reasonable ECO is going to refuse a visa because of a minor immaterial error on a checklist. If the documents you provided are enough to issue the visa, checking off additional unnecessary items without providing them will not doom your application.
None, just commonsense and a history of making minor mistakes on previous visa applications.