Gmail never deletes when accessed from Outlook or other email clients. The only way to delete is to signon directly thru your browser and delete each email. The premise of Gmail is to never have to manage emails. That is why they give 8gb of storage.
In the Gmail settings you can chose to move emails to all mail folder after they have been viewed or leave them in the inbox.
System Manufacturer/Model Number Home Built OS Windows 7 SP1 x64 CPU AMD 9850 X4 Motherboard ASUS Memory Corsair Graphics Card ATI Radeon Sound Card Sigmatel Monitor(s) Displays Dell Screen Resolution 1600X900
Cooling Corsair H60 Hard Drives (1) WD 1TB Internet Speed UVerse 12MB
System Manufacturer/Model Number tw33k OS Windows 7 Ultimate (x64) SP1 CPU Intel 3770k 4.6GHz Motherboard ASUS Maximus V Formula Memory 8GB (2x 4GB) Crucial Ballistix Graphics Card Sapphire 7950 (1060/1600) Sound Card On Board Realtek HD Audio Monitor(s) Displays 27" Acer B273HU (via HDMI) Screen Resolution 2048 x 1152
Keyboard Microsoft Wireless 5000 Mouse Microsoft Wireless 5000 PSU Corsair AX750 Gold Case Corsair Obsidian 800DW Cooling Corsair H100 (2x AP-121/2x UK-3000 push/pull) Hard Drives Crucial M4 128GB
2TB WD Black
1TB Samsung F3 SATA
1TB WD Elite External
2TB WD USB 3.0 Internet Speed 5mb/s Other Info Logitech z-2300 2.1 speakers
Lamptron FC-5 v2