But the Blues boss is confident his club’s recruitment will improve as he and his staff settle into life at Fratton Park.
Cowley has admitted his Fratton overhaul took place at a breakneck speed this summer, after arriving as Kenny Jackett’s successor in March.
A total of 15 players were brought in with 18 departing, as the Londoner ripped up his playing options.
Pompey held their latest recruitment meeting on Thursday to assess what could have been done better, and plot the way forward in January.
That meant some honest reflection on the work done to date, while looking at how things can be improved from January 1.
Cowley said: ‘We had our monthly recruitment meeting and it was really productive.
‘It was obviously off the back of the last window shutting.
‘There’s always an opportunity to do a review, review your process, way of working and decisions you made.
‘We also can look towards the next window.
‘It’s a forever evolving piece of work really
‘We only arrived mid-March, so were really behind with regard to the summer window.
‘We didn’t have the work we would’ve liked to have in place, with how the season finished and things were.
‘So we had to play catch-up all summer.
‘There was obviously a lot of change at the club, with Andy Cullen in particular coming in for Mark Catlin.
‘It’s our first summer with the club and Andy Cullen’s first season as CEO.
‘Naturally, you’re trying to build these relationships within the club and find a way of working that suits everybody.
‘There’s been lots of learning take place and it’s important we review intelligently so we can find out what worked, what we did well and the areas we can improve.’
As well as planning for January, Cowley outlined how Pompey will also be looking towards next summer and beyond as they lay down their strategy for tweaking the squad.
He added: ‘You want to try to plan for the next three windows. That’s what you’re always trying to do.
‘The nature of being a League One club at the moment means most of the player are on relatively short contracts.
‘So you’re always aware of that, whether you’re discussing players who are coming out of contract or discussing potential targets.
‘The longer you spend at a club the clearer things become and the better your feel is for it.
‘The first window is always your toughest, and it always gets easier the longer you spend at a club.’
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