Speculation: Wenger seems to, more often than not, wait for the last moment in the transfer window to do any business, if at all.
IMO before the transfer window started we had our best chance of winning the PL in many years. If I had to arbitrarily handicap our chances relative to the main other contenders I would say we had a 25% chance with the other 75% being divided between City and Chelsea.
I had hoped that with the signing of a quality striker we could have increased this percentage to 33% or better.
With Walcott out and assuming no striker of serious caliber coming in and no other serious attacking reinforcement coming in I would expect our chances to drop to 15% or less and to go to 5% should Giroud get injured over during the next two grueling months.
I have no problem with not signing a top quality striker this window and I would consider 3rd place a solid year provided we will end the year closer to 1st place than in previous years.
I would have serious problems if we don't go out next summer and sign a serious striker for next season. To pair Ozil with Giroud is a little like asking Fred Astaire to dance with Katie Price, he might make her look good but he won't be able to turn her into Ginger Rgoers.
To maximize our investment in our talented midfield we need to give them a striker who will put chances away more often than not, strikers like Aguiro, Suarez, RVP, Lewondowski, Falcao, Cavani, Costa etc.
I am fully prepared to end the season in 3rd (and don't care at all about the FA cup) and still consider this our most enjoyable season in a long time, having spend so much time in 1st deservedly. I am not prepared for Ozil to be our only ready to deliver top level purchase and for our obvious upward trend to be a one year trend.