What causes slow load times on Adobe Target experiences?

• Asset sizes (i.e. optimize your files)
• Test asset coding (i.e. make sure your code isn't looking for something that's not there or optimized)
• Network speed
• Excessive experiences on the same DOM elements (i.e. 100+)
• Blocked endpoints (i.e. mboxedge28.tt.omtrdc.net)

What else should be listed here that I missed?