The claim you're making is a general one about Wenger being focused on small deals to the detriment of big ones.
The general response is that the small deals are more straightforward to conclude because there are fewer contingencies. It's not just us doing business on deadline day.
Like it or not from a "focus" perspective, Arsenal actually needs to be investing more in players who do nothing to help our squad—we should adopt the Chelsea model where we buy a spread of £5-15m players and send them on loan, they're making a killing doing it.