The DWR (Temporary water repellant) treatment beads water away from the waterproof/breathable membrane. Once the beading stops, the fabric and membrane soaks up water, remaining waterproof but not breathable. It takes hours to dry off.
DWR effect can be destroyed by detergent washes. Use a soap-based cleaner. You can get special outdoor cleaning stuff but soap flakes or soap liquid work well. If you have used a detergent wash, re-wash in soap.
If you dryclean the garment, rewash with soap.
You can restore DWR with heat. Gortex recommend ironing the surface.
I have used Nikwax for many years. Some drycleaners can also apply a DWR.