While there's a whole bunch of reasons, the main two in my opinion loyalty is at an all time low is because loyalty take a certain amount of trust and time to develop...
We live in a "ME! ME! ME!" culture that encourages self above all else. It's less "How can I help this person?" and waaaaaay more "If I help this person, what will they do to benefit me?" People so egocentric, they think the other person thinks the exact same way, and will try and get over on a muthafukka, so they do it 1st...
"Nothin personal, just business... :birdaman:"
"What the hell?!? Why you divorce me?!?! I thought things were great!

"
"They were... just wanted to cut my losses... gotta get mine, right?

"
We also live in a 'microwave' culture that wants everything immediately. Information is a the tap of a smart phone; outside of suburbs and 3rd world countries, food is literally a block away.
Loyalty takes an extensive amount of time.
Like, years.
People want a home cooked meal in a half hour, you see on FB and IG "I want that 'Damn, y'all still together?!?' relationship..." But want that shyt in like, a month.
Two of my closest potnas (nh) I now have known for 7 years and 5 years. Due to all the shyt we been through, they know I got their backs, and I got theirs.
It takes time, people.
But what do I know?
